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/routers/dashboard.py

@@ -1,10 +1,9 @@
 from fastapi import APIRouter, Request, Depends
-from fastapi.templating import Jinja2Templates
 
 from backend.services.snapshot import emit_status_snapshot
+from backend.templates_config import templates
 
 router = APIRouter()
-templates = Jinja2Templates(directory="templates")
 
 
 @router.get("/dashboard/active")