feat(notifications): implement notification system with CRUD operations and UI integration

server/config/database.js

@@ -617,6 +617,38 @@ export async function initDatabase() {
     `);
   }
 
+  // ── Notifications table ──────────────────────────────────────────────────
+  if (isPostgres) {
+    await db.exec(`
+      CREATE TABLE IF NOT EXISTS notifications (
+        id SERIAL PRIMARY KEY,
+        user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+        type TEXT NOT NULL,
+        title TEXT NOT NULL,
+        body TEXT,
+        link TEXT,
+        read INTEGER DEFAULT 0,
+        created_at TIMESTAMP DEFAULT NOW()
+      );
+      CREATE INDEX IF NOT EXISTS idx_notifications_user_id ON notifications(user_id);
+    `);
+  } else {
+    await db.exec(`
+      CREATE TABLE IF NOT EXISTS notifications (
+        id INTEGER PRIMARY KEY AUTOINCREMENT,
+        user_id INTEGER NOT NULL,
+        type TEXT NOT NULL,
+        title TEXT NOT NULL,
+        body TEXT,
+        link TEXT,
+        read INTEGER DEFAULT 0,
+        created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+        FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
+      );
+      CREATE INDEX IF NOT EXISTS idx_notifications_user_id ON notifications(user_id);
+    `);
+  }
+
   // ── Default admin (only on very first start) ────────────────────────────
   const adminAlreadySeeded = await db.get("SELECT value FROM settings WHERE key = 'admin_seeded'");
   if (!adminAlreadySeeded) {