feat(ui): introduce shared PageSidebar for Settings and Admin

Replaces the inline tab bar on SettingsPage and AdminPage with a
responsive sidebar layout (left nav on desktop, hamburger drawer on
mobile). Each tab gets a lucide-react icon for quick scanning. Both
pages drop max-w-6xl so the panel fills the viewport.

client/src/components/Layout/PageSidebar.tsx

@@ -0,0 +1,210 @@
+import React, { useState, useEffect, useRef } from 'react'
+import { Menu, X, type LucideIcon } from 'lucide-react'
+
+export interface PageSidebarTab {
+  id: string
+  label: string
+  icon: LucideIcon
+}
+
+interface PageSidebarProps {
+  /** Uppercase label shown above the tab list, e.g. "SETTINGS". */
+  sidebarLabel: string
+  tabs: PageSidebarTab[]
+  activeTab: string
+  onTabChange: (id: string) => void
+  children: React.ReactNode
+  /** Small text at the very bottom of the sidebar (e.g. "v3.0 · self-hosted"). */
+  footer?: React.ReactNode
+}
+
+/**
+ * Left-sidebar + right-panel layout used by the Settings and Admin pages.
+ *
+ * Desktop (>=1024px): sidebar is always visible at 260px; panel fills rest.
+ * Mobile: sidebar collapses behind a hamburger at the top of the panel; tap
+ * the hamburger to slide the sidebar in as an overlay, tap a tab to close.
+ */
+export default function PageSidebar({
+  sidebarLabel,
+  tabs,
+  activeTab,
+  onTabChange,
+  children,
+  footer,
+}: PageSidebarProps): React.ReactElement {
+  const [mobileOpen, setMobileOpen] = useState(false)
+  const activeLabel = tabs.find(t => t.id === activeTab)?.label ?? ''
+
+  // Close the mobile drawer on Escape or on outside click.
+  const drawerRef = useRef<HTMLDivElement>(null)
+  useEffect(() => {
+    if (!mobileOpen) return
+    const onKey = (e: KeyboardEvent) => { if (e.key === 'Escape') setMobileOpen(false) }
+    window.addEventListener('keydown', onKey)
+    return () => window.removeEventListener('keydown', onKey)
+  }, [mobileOpen])
+
+  return (
+    <div
+      className="rounded-2xl overflow-hidden flex flex-col lg:flex-row relative"
+      style={{
+        background: 'var(--bg-card)',
+        border: '1px solid var(--border-primary)',
+        minHeight: 'min(820px, calc(100vh - var(--nav-h) - 120px))',
+      }}
+    >
+      {/* Mobile top bar with hamburger */}
+      <div
+        className="lg:hidden flex items-center justify-between px-4 py-3 border-b"
+        style={{ borderColor: 'var(--border-primary)' }}
+      >
+        <button
+          onClick={() => setMobileOpen(true)}
+          className="w-9 h-9 rounded-lg flex items-center justify-center transition-colors hover:bg-[var(--bg-hover)]"
+          aria-label="Open navigation"
+          style={{ color: 'var(--text-primary)' }}
+        >
+          <Menu size={18} />
+        </button>
+        <div className="flex items-center gap-2 text-sm font-semibold" style={{ color: 'var(--text-primary)' }}>
+          {activeLabel}
+        </div>
+        <div className="w-9" />
+      </div>
+
+      {/* Desktop sidebar (always visible on lg) */}
+      <aside
+        className="hidden lg:flex flex-col shrink-0 relative"
+        style={{
+          width: 260,
+          background: 'var(--bg-secondary)',
+          borderRight: '1px solid var(--border-primary)',
+          padding: '24px 14px',
+        }}
+      >
+        <SidebarInner
+          sidebarLabel={sidebarLabel}
+          tabs={tabs}
+          activeTab={activeTab}
+          onTabChange={onTabChange}
+          footer={footer}
+        />
+      </aside>
+
+      {/* Mobile drawer */}
+      {mobileOpen && (
+        <>
+          <div
+            className="lg:hidden fixed inset-0 z-40"
+            style={{ background: 'rgba(0,0,0,0.35)' }}
+            onClick={() => setMobileOpen(false)}
+          />
+          <aside
+            ref={drawerRef}
+            className="lg:hidden fixed top-0 left-0 bottom-0 z-50 flex flex-col shadow-2xl"
+            style={{
+              width: 280,
+              background: 'var(--bg-secondary)',
+              padding: '18px 14px',
+            }}
+          >
+            <div className="flex items-center justify-between mb-3 px-2">
+              <span
+                className="text-[11px] font-bold tracking-widest uppercase"
+                style={{ color: 'var(--text-muted)' }}
+              >
+                {sidebarLabel}
+              </span>
+              <button
+                onClick={() => setMobileOpen(false)}
+                className="w-8 h-8 rounded-lg flex items-center justify-center transition-colors hover:bg-[var(--bg-hover)]"
+                aria-label="Close navigation"
+                style={{ color: 'var(--text-primary)' }}
+              >
+                <X size={16} />
+              </button>
+            </div>
+            <SidebarInner
+              sidebarLabel={null}
+              tabs={tabs}
+              activeTab={activeTab}
+              onTabChange={(id) => {
+                onTabChange(id)
+                setMobileOpen(false)
+              }}
+              footer={footer}
+            />
+          </aside>
+        </>
+      )}
+
+      {/* Panel */}
+      <div className="flex-1 min-w-0" style={{ padding: '26px 28px' }}>
+        {children}
+      </div>
+    </div>
+  )
+}
+
+function SidebarInner({
+  sidebarLabel,
+  tabs,
+  activeTab,
+  onTabChange,
+  footer,
+}: {
+  sidebarLabel: string | null
+  tabs: PageSidebarTab[]
+  activeTab: string
+  onTabChange: (id: string) => void
+  footer?: React.ReactNode
+}): React.ReactElement {
+  return (
+    <>
+      {sidebarLabel && (
+        <div
+          className="text-[11px] font-bold tracking-widest uppercase mb-3 px-3"
+          style={{ color: 'var(--text-muted)' }}
+        >
+          {sidebarLabel}
+        </div>
+      )}
+      <nav className="flex flex-col gap-1 flex-1">
+        {tabs.map((tab) => {
+          const Icon = tab.icon
+          const active = tab.id === activeTab
+          return (
+            <button
+              key={tab.id}
+              onClick={() => onTabChange(tab.id)}
+              className="flex items-center gap-2.5 px-3 py-2 rounded-lg text-sm text-left transition-colors"
+              style={{
+                background: active ? 'var(--bg-hover)' : 'transparent',
+                color: active ? 'var(--text-primary)' : 'var(--text-secondary)',
+                fontWeight: active ? 600 : 500,
+              }}
+              onMouseEnter={(e) => {
+                if (!active) e.currentTarget.style.background = 'var(--bg-hover)'
+              }}
+              onMouseLeave={(e) => {
+                if (!active) e.currentTarget.style.background = 'transparent'
+              }}
+            >
+              <Icon size={16} className="shrink-0" />
+              <span className="truncate">{tab.label}</span>
+            </button>
+          )
+        })}
+      </nav>
+      {footer && (
+        <div
+          className="mt-4 pt-3 px-3 text-[10px] tracking-wide"
+          style={{ color: 'var(--text-faint)', borderTop: '1px solid var(--border-primary)' }}
+        >
+          {footer}
+        </div>
+      )}
+    </>
+  )
+}

client/src/pages/AdminPage.tsx

@@ -20,8 +20,9 @@ import PackingTemplateManager from '../components/Admin/PackingTemplateManager'
 import AuditLogPanel from '../components/Admin/AuditLogPanel'
 import AdminMcpTokensPanel from '../components/Admin/AdminMcpTokensPanel'
 import PermissionsPanel from '../components/Admin/PermissionsPanel'
-import { Users, Map, Briefcase, Shield, Trash2, Edit2, FileText, Eye, EyeOff, Save, CheckCircle, XCircle, Loader2, UserPlus, ArrowUpCircle, ExternalLink, Download, Sun, Link2, Copy, Plus, RefreshCw, AlertTriangle } from 'lucide-react'
+import { Users, Map, Briefcase, Shield, Trash2, Edit2, FileText, Eye, EyeOff, Save, CheckCircle, XCircle, Loader2, UserPlus, ArrowUpCircle, ExternalLink, Download, Sun, Link2, Copy, Plus, RefreshCw, AlertTriangle, SlidersHorizontal, UserCog, Puzzle, Settings as SettingsIcon, Bell, Database, ScrollText, KeyRound, GitBranch, Bug } from 'lucide-react'
 import CustomSelect from '../components/shared/CustomSelect'
+import PageSidebar, { type PageSidebarTab } from '../components/Layout/PageSidebar'
 
 interface AdminUser {
   id: number
@@ -183,18 +184,18 @@ export default function AdminPage(): React.ReactElement {
   const hour12 = useSettingsStore(s => s.settings.time_format) === '12h'
   const mcpEnabled = useAddonStore(s => s.isEnabled('mcp'))
   const devMode = useAuthStore(s => s.devMode)
-  const TABS = [
-    { id: 'users', label: t('admin.tabs.users') },
-    { id: 'config', label: t('admin.tabs.config') },
-    { id: 'defaults', label: t('admin.tabs.defaults') },
-    { id: 'addons', label: t('admin.tabs.addons') },
-    { id: 'settings', label: t('admin.tabs.settings') },
-    { id: 'notifications', label: t('admin.tabs.notifications') },
-    { id: 'backup', label: t('admin.tabs.backup') },
-    { id: 'audit', label: t('admin.tabs.audit') },
-    ...(mcpEnabled ? [{ id: 'mcp-tokens', label: t('admin.tabs.mcpTokens') }] : []),
-    { id: 'github', label: t('admin.tabs.github') },
-    ...(devMode ? [{ id: 'dev-notifications', label: 'Dev: Notifications' }] : []),
+  const TABS: PageSidebarTab[] = [
+    { id: 'users', label: t('admin.tabs.users'), icon: Users },
+    { id: 'config', label: t('admin.tabs.config'), icon: SlidersHorizontal },
+    { id: 'defaults', label: t('admin.tabs.defaults'), icon: UserCog },
+    { id: 'addons', label: t('admin.tabs.addons'), icon: Puzzle },
+    { id: 'settings', label: t('admin.tabs.settings'), icon: SettingsIcon },
+    { id: 'notifications', label: t('admin.tabs.notifications'), icon: Bell },
+    { id: 'backup', label: t('admin.tabs.backup'), icon: Database },
+    { id: 'audit', label: t('admin.tabs.audit'), icon: ScrollText },
+    ...(mcpEnabled ? [{ id: 'mcp-tokens', label: t('admin.tabs.mcpTokens'), icon: KeyRound }] : []),
+    { id: 'github', label: t('admin.tabs.github'), icon: GitBranch },
+    ...(devMode ? [{ id: 'dev-notifications', label: 'Dev: Notifications', icon: Bug }] : []),
   ]
 
   const [activeTab, setActiveTab] = useState<string>('users')
@@ -500,7 +501,7 @@ export default function AdminPage(): React.ReactElement {
       <Navbar />
 
       <div style={{ paddingTop: 'var(--nav-h)' }}>
-        <div className="max-w-6xl mx-auto px-4 py-8">
+        <div className="w-full px-4 sm:px-6 lg:px-8 py-8">
           {/* Header */}
           <div className="flex items-center gap-3 mb-6">
             <div className="w-10 h-10 bg-slate-100 rounded-xl flex items-center justify-center">
@@ -586,24 +587,15 @@ export default function AdminPage(): React.ReactElement {
             </div>
           )}
 
-          {/* Tabs */}
-          <div className="grid grid-cols-3 sm:flex gap-1 mb-6 rounded-xl p-1" style={{ background: 'var(--bg-card)', border: '1px solid var(--border-primary)' }}>
-            {TABS.map(tab => (
-              <button
-                key={tab.id}
-                onClick={() => setActiveTab(tab.id)}
-                className={`px-3 sm:px-4 py-2 text-xs sm:text-sm font-medium rounded-lg transition-colors ${
-                  activeTab === tab.id
-                    ? 'bg-slate-900 text-white'
-                    : 'text-slate-600 hover:text-slate-900 hover:bg-slate-50'
-                }`}
-              >
-                {tab.label}
-              </button>
-            ))}
-          </div>
-
-          {/* Tab content */}
+          {/* Sidebar layout — nav on the left, active panel on the right */}
+          <PageSidebar
+            sidebarLabel={t('admin.title').toUpperCase()}
+            tabs={TABS}
+            activeTab={activeTab}
+            onTabChange={setActiveTab}
+            footer="admin · self-hosted"
+          >
+            {/* Tab content */}
           {activeTab === 'users' && (
             <div className="bg-white rounded-xl border border-slate-200 overflow-hidden">
               <div className="p-5 border-b border-slate-100 flex items-center justify-between">
@@ -1618,6 +1610,7 @@ export default function AdminPage(): React.ReactElement {
           {activeTab === 'defaults' && <DefaultUserSettingsTab />}
 
           {activeTab === 'dev-notifications' && <DevNotificationsPanel />}
+          </PageSidebar>
         </div>
       </div>
 

client/src/pages/SettingsPage.tsx

@@ -1,10 +1,11 @@
 import React, { useState, useEffect } from 'react'
 import { useSearchParams } from 'react-router-dom'
-import { Settings } from 'lucide-react'
+import { Settings, Palette, Map, Bell, Plug, CloudOff, User, Info } from 'lucide-react'
 import { useTranslation } from '../i18n'
 import { authApi } from '../api/client'
 import { useAddonStore } from '../store/addonStore'
 import Navbar from '../components/Layout/Navbar'
+import PageSidebar, { type PageSidebarTab } from '../components/Layout/PageSidebar'
 import DisplaySettingsTab from '../components/Settings/DisplaySettingsTab'
 import MapSettingsTab from '../components/Settings/MapSettingsTab'
 import NotificationsTab from '../components/Settings/NotificationsTab'
@@ -37,14 +38,18 @@ export default function SettingsPage(): React.ReactElement {
     }
   }, [searchParams])
 
-  const TABS = [
-    { id: 'display', label: t('settings.tabs.display') },
-    { id: 'map', label: t('settings.tabs.map') },
-    { id: 'notifications', label: t('settings.tabs.notifications') },
-    ...(hasIntegrations ? [{ id: 'integrations', label: t('settings.tabs.integrations') }] : []),
-    { id: 'offline', label: t('settings.tabs.offline') },
-    { id: 'account', label: t('settings.tabs.account') },
-    ...(appVersion ? [{ id: 'about', label: t('settings.tabs.about') }] : []),
+  const tabs: PageSidebarTab[] = [
+    { id: 'display', label: t('settings.tabs.display'), icon: Palette },
+    { id: 'map', label: t('settings.tabs.map'), icon: Map },
+    { id: 'notifications', label: t('settings.tabs.notifications'), icon: Bell },
+    ...(hasIntegrations
+      ? [{ id: 'integrations', label: t('settings.tabs.integrations'), icon: Plug }]
+      : []),
+    { id: 'offline', label: t('settings.tabs.offline'), icon: CloudOff },
+    { id: 'account', label: t('settings.tabs.account'), icon: User },
+    ...(appVersion
+      ? [{ id: 'about', label: t('settings.tabs.about'), icon: Info }]
+      : []),
   ]
 
   return (
@@ -52,7 +57,7 @@ export default function SettingsPage(): React.ReactElement {
       <Navbar />
 
       <div style={{ paddingTop: 'var(--nav-h)' }}>
-        <div className="max-w-6xl mx-auto px-4 py-8">
+        <div className="w-full px-4 sm:px-6 lg:px-8 py-8">
           {/* Header */}
           <div className="flex items-center gap-3 mb-6">
             <div className="w-10 h-10 rounded-xl flex items-center justify-center" style={{ background: 'var(--bg-tertiary)' }}>
@@ -64,33 +69,24 @@ export default function SettingsPage(): React.ReactElement {
             </div>
           </div>
 
-          {/* Tab bar */}
-          <div className="grid grid-cols-3 sm:flex gap-1 mb-6 rounded-xl p-1" style={{ background: 'var(--bg-card)', border: '1px solid var(--border-primary)' }}>
-            {TABS.map(tab => (
-              <button
-                key={tab.id}
-                onClick={() => setActiveTab(tab.id)}
-                className={`px-3 sm:px-4 py-2 text-xs sm:text-sm font-medium rounded-lg transition-colors ${
-                  activeTab === tab.id
-                    ? 'bg-slate-900 text-white'
-                    : 'text-slate-600 hover:text-slate-900 hover:bg-slate-50'
-                }`}
-              >
-                {tab.label}
-              </button>
-            ))}
-          </div>
-
-          {/* Tab content */}
-          {activeTab === 'display' && <DisplaySettingsTab />}
-          {activeTab === 'map' && <MapSettingsTab />}
-          {activeTab === 'notifications' && <NotificationsTab />}
-          {activeTab === 'integrations' && hasIntegrations && <IntegrationsTab />}
-          {activeTab === 'offline' && <OfflineTab />}
-          {activeTab === 'account' && <AccountTab />}
-          {activeTab === 'about' && appVersion && <AboutTab appVersion={appVersion} />}
+          {/* Sidebar layout */}
+          <PageSidebar
+            sidebarLabel={t('settings.title').toUpperCase()}
+            tabs={tabs}
+            activeTab={activeTab}
+            onTabChange={setActiveTab}
+            footer={appVersion ? `v${appVersion} · self-hosted` : 'self-hosted'}
+          >
+            {activeTab === 'display' && <DisplaySettingsTab />}
+            {activeTab === 'map' && <MapSettingsTab />}
+            {activeTab === 'notifications' && <NotificationsTab />}
+            {activeTab === 'integrations' && hasIntegrations && <IntegrationsTab />}
+            {activeTab === 'offline' && <OfflineTab />}
+            {activeTab === 'account' && <AccountTab />}
+            {activeTab === 'about' && appVersion && <AboutTab appVersion={appVersion} />}
+          </PageSidebar>
         </div>
       </div>
     </div>
   )
-}
+}