Migrate Angular 2 to Angular 19 with standalone components

- Upgrade Angular, Firebase, and AngularFire to latest versions
- Replace NgModules with standalone components and bootstrapApplication
- Replace angular-cli.json with angular.json and ESLint
- Add Firebase App Check with reCAPTCHA v3 for abuse protection
- Move Firebase config out of version control (firebaseConfig.example.ts)
- Fix AngularFire injection context errors using runInInjectionContext
- Implement drag-and-drop reordering within and across columns
- Add inline editing for card title and description
- Add subtask deletion with confirmation modal
- Refresh UI with modern card-based look and feel

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.vscode/launch.json

@@ -0,0 +1,20 @@
+{
+  // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+  "version": "0.2.0",
+  "configurations": [
+    {
+      "name": "ng serve",
+      "type": "chrome",
+      "request": "launch",
+      "preLaunchTask": "npm: start",
+      "url": "http://localhost:4200/"
+    },
+    {
+      "name": "ng test",
+      "type": "chrome",
+      "request": "launch",
+      "preLaunchTask": "npm: test",
+      "url": "http://localhost:9876/debug.html"
+    }
+  ]
+}