feat: show transport bookings in day plan timeline — closes #37

Transport reservations (flights, trains, buses, cars, cruises) now appear
directly in the day plan timeline based on their reservation date/time.

- Transport cards display inline with places and notes, sorted by time
- Click to open detail modal with all booking data and linked files
- Persistent positioning via new day_plan_position field on reservations
- Free drag & drop: places can be moved between/around transport entries
- Arrow reorder works on the full visual list including transports
- Timed places show confirmation popup when reorder breaks chronology
- Custom delete confirmation popup for reservations
- DB migration adds day_plan_position column to reservations table
- New batch endpoint PUT /reservations/positions for position updates
- i18n keys added for DE and EN

client/src/components/Planner/ReservationsPanel.tsx

@@ -1,4 +1,5 @@
 import { useState, useMemo } from 'react'
+import ReactDOM from 'react-dom'
 import { useTripStore } from '../../store/tripStore'
 import { useSettingsStore } from '../../store/settingsStore'
 import { useToast } from '../shared/Toast'
@@ -67,13 +68,14 @@ function ReservationCard({ r, tripId, onEdit, onDelete, files = [], onNavigateTo
   const confirmed = r.status === 'confirmed'
   const attachedFiles = files.filter(f => f.reservation_id === r.id || (f.linked_reservation_ids || []).includes(r.id))
   const linked = r.assignment_id ? assignmentLookup[r.assignment_id] : null
+  const [showDeleteConfirm, setShowDeleteConfirm] = useState(false)
 
   const handleToggle = async () => {
     try { await toggleReservationStatus(tripId, r.id) }
     catch { toast.error(t('reservations.toast.updateError')) }
   }
   const handleDelete = async () => {
-    if (!confirm(t('reservations.confirm.delete', { name: r.title }))) return
+    setShowDeleteConfirm(false)
     try { await onDelete(r.id) } catch { toast.error(t('reservations.toast.deleteError')) }
   }
 
@@ -104,7 +106,7 @@ function ReservationCard({ r, tripId, onEdit, onDelete, files = [], onNavigateTo
           onMouseLeave={e => e.currentTarget.style.color = 'var(--text-faint)'}>
           <Pencil size={11} />
         </button>
-        <button onClick={handleDelete} title={t('common.delete')} style={{ padding: 3, background: 'none', border: 'none', cursor: 'pointer', color: 'var(--text-faint)', display: 'flex', flexShrink: 0 }}
+        <button onClick={() => setShowDeleteConfirm(true)} title={t('common.delete')} style={{ padding: 3, background: 'none', border: 'none', cursor: 'pointer', color: 'var(--text-faint)', display: 'flex', flexShrink: 0 }}
           onMouseEnter={e => e.currentTarget.style.color = '#ef4444'}
           onMouseLeave={e => e.currentTarget.style.color = 'var(--text-faint)'}>
           <Trash2 size={11} />
@@ -227,6 +229,46 @@ function ReservationCard({ r, tripId, onEdit, onDelete, files = [], onNavigateTo
           </div>
         </div>
       )}
+      {/* Delete confirmation popup */}
+      {showDeleteConfirm && ReactDOM.createPortal(
+        <div style={{
+          position: 'fixed', inset: 0, zIndex: 1000,
+          display: 'flex', alignItems: 'center', justifyContent: 'center',
+          background: 'rgba(0,0,0,0.3)', backdropFilter: 'blur(3px)',
+        }} onClick={() => setShowDeleteConfirm(false)}>
+          <div style={{
+            width: 340, background: 'var(--bg-card)', borderRadius: 16,
+            boxShadow: '0 16px 48px rgba(0,0,0,0.22)', padding: '22px 22px 18px',
+            display: 'flex', flexDirection: 'column', gap: 12,
+          }} onClick={e => e.stopPropagation()}>
+            <div style={{ display: 'flex', alignItems: 'center', gap: 10 }}>
+              <div style={{
+                width: 36, height: 36, flexShrink: 0, display: 'flex', alignItems: 'center', justifyContent: 'center',
+                borderRadius: '50%', background: 'rgba(239,68,68,0.12)',
+              }}>
+                <Trash2 size={18} strokeWidth={1.8} color="#ef4444" />
+              </div>
+              <div style={{ fontSize: 14, fontWeight: 600, color: 'var(--text-primary)' }}>
+                {t('reservations.confirm.deleteTitle')}
+              </div>
+            </div>
+            <div style={{ fontSize: 12.5, color: 'var(--text-secondary)', lineHeight: 1.5 }}>
+              {t('reservations.confirm.deleteBody', { name: r.title })}
+            </div>
+            <div style={{ display: 'flex', gap: 8, justifyContent: 'flex-end', marginTop: 4 }}>
+              <button onClick={() => setShowDeleteConfirm(false)} style={{
+                fontSize: 12, background: 'none', border: '1px solid var(--border-primary)',
+                borderRadius: 8, padding: '6px 14px', cursor: 'pointer', color: 'var(--text-muted)', fontFamily: 'inherit',
+              }}>{t('common.cancel')}</button>
+              <button onClick={handleDelete} style={{
+                fontSize: 12, background: '#ef4444', color: 'white',
+                border: 'none', borderRadius: 8, padding: '6px 16px', cursor: 'pointer', fontWeight: 600, fontFamily: 'inherit',
+              }}>{t('common.confirm')}</button>
+            </div>
+          </div>
+        </div>,
+        document.body
+      )}
     </div>
   )
 }