feat: Implement Entity Suggestion Manager and Modal components

- Added EntitySuggestionManager.vue to manage entity suggestions and authentication.
- Created EntitySuggestionModal.vue for displaying suggestions and adding new entities.
- Integrated AuthManager for user authentication within the suggestion modal.
- Enhanced signal handling in start-servers.sh for graceful shutdown of servers.
- Improved server startup script to ensure proper cleanup and responsiveness to termination signals.
- Added documentation for signal handling fixes and usage instructions.

backend/setup_social_providers.py

@@ -17,22 +17,22 @@ print("Cleared existing social apps")
 
 # Create Google social app
 google_app = SocialApp.objects.create(
-    provider='google',
-    name='Google',
-    client_id='demo-google-client-id.apps.googleusercontent.com',
-    secret='demo-google-client-secret',
-    key='',  # Not used for Google
+    provider="google",
+    name="Google",
+    client_id="demo-google-client-id.apps.googleusercontent.com",
+    secret="demo-google-client-secret",
+    key="",  # Not used for Google
 )
 google_app.sites.add(site)
 print("✅ Created Google social app")
 
 # Create Discord social app
 discord_app = SocialApp.objects.create(
-    provider='discord',
-    name='Discord',
-    client_id='demo-discord-client-id',
-    secret='demo-discord-client-secret',
-    key='',  # Not used for Discord
+    provider="discord",
+    name="Discord",
+    client_id="demo-discord-client-id",
+    secret="demo-discord-client-secret",
+    key="",  # Not used for Discord
 )
 discord_app.sites.add(site)
 print("✅ Created Discord social app")