feat(scheduling): persist notifications, batch notify flow, dedup protection

- Add tab_scheduling_notifications table with bootstrap via ensureSchedulingTables()
- Notify endpoint rewritten: dedup by (suggestion_id, candidate_plate), history list, PATCH /:id for execute/cancel lifecycle
- Batch notify endpoint returns success/skipped/failed counts
- Suggestions response now carries notificationId + notificationStatus per candidate (joined from active-notification map)
- UI: select mode with checkboxes, floating action bar, confirmation modal listing each swap; already-notified items are dimmed and skipped
- Detail view badges show sent/executed state, preventing duplicate notify

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/server/routes/scheduling/suggestions.ts

@@ -5,6 +5,7 @@ import { fetchVehicleInfoMap } from '../mileage/vehicle-info.js';
 import { mapRegion } from '../vehicles.js';
 import { filterByPermission, maskCustomerNames } from '../../auth/permissions.js';
 import { classifyVehicle, generateSuggestions } from './algorithm.js';
+import { fetchActiveNotificationMap } from './notify.js';
 import type { EnrichedVehicle, InventoryVehicle, SchedulingResponse, SchedulingSummary } from './types.js';
 import type { AuthUser } from '../../auth/types.js';
 
@@ -275,6 +276,19 @@ app.get('/', async (c) => {
     // ---- Run algorithm ----
     const { suggestions, summary } = generateSuggestions(enrichedVehicles, inventoryVehicles);
 
+    // ---- Attach notification status to candidates ----
+    const notificationMap = await fetchActiveNotificationMap();
+    for (const s of suggestions) {
+      for (const c of s.candidates) {
+        const key = `${s.id}::${c.plateNumber}`;
+        const notif = notificationMap.get(key);
+        if (notif) {
+          c.notificationId = notif.id;
+          c.notificationStatus = notif.status;
+        }
+      }
+    }
+
     // ---- Permission filtering & customer name masking ----
     const user = (c as any).get('user') as AuthUser | undefined;