feat(plugins): redesign the admin plugins page — search, filters, cleaner cards

The panel was cramped and hard to scan. Rebuilt it as a proper management
surface:

- A segmented Installed/Discover switch with counts, and a real toolbar:
  search, filter by type, filter by status (active/off/update/error), and
  sort (name/recent/updates first).
- An "N updates available · Update all" bar.
- Installed rows are tidied up: a single health dot on the icon tile
  instead of a wall of badges, and capability chips underneath that show
  what each plugin can actually reach at a glance (reads your trips,
  dashboard widget, the hosts it talks to) — the reach is now visible
  without opening anything. Update, toggle and a ⋯ menu (restart, errors,
  source, uninstall) sit on the right.
- The registry browser is now an App-Store-style card grid: screenshot
  with the plugin's icon chip, a reviewed badge, consistent heights.
- The detail dialog gained "What it can access", "Connects to" and a
  details grid (version, size, requires, reviewed).

To feed the capability chips, the installed list now returns each plugin's
declared permissions and capabilities. New copy is in all 22 locales.

server/tests/unit/plugins/plugins-service.test.ts

@@ -9,7 +9,7 @@ const { testDb } = vi.hoisted(() => {
   const db = new Database(':memory:');
   db.exec(`CREATE TABLE plugins (
     id TEXT PRIMARY KEY, name TEXT, description TEXT, type TEXT, icon TEXT, version TEXT,
-    status TEXT, enabled INTEGER DEFAULT 0, last_error TEXT, reviewed_at TEXT, source_repo TEXT, config TEXT DEFAULT '{}', capabilities TEXT DEFAULT '{}', updated_at TEXT,
+    status TEXT, enabled INTEGER DEFAULT 0, last_error TEXT, reviewed_at TEXT, source_repo TEXT, config TEXT DEFAULT '{}', permissions TEXT DEFAULT '[]', capabilities TEXT DEFAULT '{}', updated_at TEXT,
     sort_order INTEGER DEFAULT 0);
     CREATE TABLE plugin_settings_fields (plugin_id TEXT, field_key TEXT, scope TEXT, secret INTEGER);
     CREATE TABLE plugin_error_log (id INTEGER PRIMARY KEY AUTOINCREMENT, plugin_id TEXT, level TEXT, message TEXT, ts TEXT DEFAULT '2026-01-01');`);