feat: Refactor template handling, improve scheduler functions, and add timezone utilities

- Moved Jinja2 template setup to a shared configuration file (templates_config.py) for consistent usage across routers.
- Introduced timezone utilities in a new module (timezone.py) to handle UTC to local time conversions and formatting.
- Updated all relevant routers to use the new shared template configuration and timezone filters.
- Enhanced templates to utilize local time formatting for various datetime fields, improving user experience with timezone awareness.

backend/main.py

@@ -58,8 +58,8 @@ app.add_middleware(
 # Mount static files
 app.mount("/static", StaticFiles(directory="backend/static"), name="static")
 
-# Setup Jinja2 templates
-templates = Jinja2Templates(directory="templates")
+# Use shared templates configuration with timezone filters
+from backend.templates_config import templates
 
 # Add custom context processor to inject environment variable into all templates
 @app.middleware("http")