feat: Add real-time notification center with WebSocket integration

- Add in-app notification system with database storage
- Implement bell icon component with unread count badge in dashboard header
- Add full Notifications page tab with pagination and filtering (All/Unread/Read)
- Implement real-time WebSocket push notifications to all connected clients
- Add notification API endpoints: GET, PUT /read, DELETE, POST /clear
- Fix critical bug in notificationService where 'status' variable was undefined
- Add Notifications route to App.js routing
- Enhanced UI with notification popup in header and dedicated full-page view
- Auto-reconnect WebSocket with 5s timeout on disconnect
- Support rich notification content with resource details and timestamps

client/package-lock.json

@@ -8,7 +8,6 @@
       "name": "client",
       "version": "0.1.0",
       "dependencies": {
-        "@testing-library/dom": "^10.4.1",
         "@testing-library/jest-dom": "^6.9.1",
         "@testing-library/react": "^16.3.0",
         "axios": "^1.13.2",
@@ -3396,6 +3395,7 @@
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       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "@babel/code-frame": "^7.10.4",
         "@babel/runtime": "^7.12.5",
@@ -3415,6 +3415,7 @@
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       "license": "Apache-2.0",
+      "peer": true,
       "dependencies": {
         "dequal": "^2.0.3"
       }
@@ -3493,7 +3494,8 @@
       "version": "5.0.4",
       "resolved": "https://registry.npmjs.org/@types/aria-query/-/aria-query-5.0.4.tgz",
       "integrity": "sha512-rfT93uj5s0PRL7EzccGMs3brplhcrghnDoV26NqKhCAS1hVo+WdNsPvE/yb6ilfr5hi2MEk6d5EWJTKdxg8jVw==",
-      "license": "MIT"
+      "license": "MIT",
+      "peer": true
     },
     "node_modules/@types/babel__core": {
       "version": "7.20.5",
@@ -6758,6 +6760,7 @@
       "resolved": "https://registry.npmjs.org/dequal/-/dequal-2.0.3.tgz",
       "integrity": "sha512-0je+qPKHEMohvfRTCEo3CrPG6cAzAYgmzKyxRiYSSDkS6eGJdyVJm7WaYA5ECaAD9wLB2T4EEeymA5aFVcYXCA==",
       "license": "MIT",
+      "peer": true,
       "engines": {
         "node": ">=6"
       }
@@ -6880,7 +6883,8 @@
       "version": "0.5.16",
       "resolved": "https://registry.npmjs.org/dom-accessibility-api/-/dom-accessibility-api-0.5.16.tgz",
       "integrity": "sha512-X7BJ2yElsnOJ30pZF4uIIDfBEVgF4XEBxL9Bxhy6dnrm5hkzqmsWHGTiHqRiITNhMyFLyAiWndIJP7Z1NTteDg==",
-      "license": "MIT"
+      "license": "MIT",
+      "peer": true
     },
     "node_modules/dom-converter": {
       "version": "0.2.0",
@@ -11407,6 +11411,7 @@
       "resolved": "https://registry.npmjs.org/lz-string/-/lz-string-1.5.0.tgz",
       "integrity": "sha512-h5bgJWpxJNswbU7qCrV0tIKQCaS3blPDrqKWx+QxzuzL1zGUzij9XCWLrSLsJPu5t+eWA/ycetzYAO5IOMcWAQ==",
       "license": "MIT",
+      "peer": true,
       "bin": {
         "lz-string": "bin/bin.js"
       }