style: fix all flake8 linter errors across app/ directory

- Run Black formatter and isort on all app/ files
- Remove unused imports (F401) across multiple files
- Add # noqa: F401 for intentional re-exports in celery_worker.py,
  tasks/__init__.py, utils.py, frontend.py, views/base.py
- Fix f-strings without placeholders (F541) in azure.py, notification.py,
  check_credentials.py, upload_to_onedrive.py, settings.py
- Fix bare except (E722) in upload_to_sftp.py
- Fix block comment format (E265) in models.py
- Move imports to top of file to fix E402 in celery_app.py, celery_worker.py
- Fix line-too-long (E501) by wrapping strings in multiple files
- Remove unused variable (F841) in upload_to_nextcloud.py

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

app/api/diagnostic.py

@@ -1,10 +1,12 @@
 """
 Diagnostic API endpoints
 """
-from fastapi import APIRouter, Request, Depends
+
 import logging
 
-from app.auth import require_login, get_current_user
+from fastapi import APIRouter, Depends, Request
+
+from app.auth import get_current_user, require_login
 from app.config import settings
 
 # Set up logging
@@ -12,6 +14,7 @@ logger = logging.getLogger(__name__)
 
 router = APIRouter()
 
+
 @router.get("/diagnostic/settings")
 @require_login
 async def diagnostic_settings(request: Request, current_user: dict = Depends(get_current_user)):
@@ -19,82 +22,85 @@ async def diagnostic_settings(request: Request, current_user: dict = Depends(get
     API endpoint to dump settings to the log and view basic config information
     This endpoint doesn't expose sensitive information like passwords or tokens
     """
-    from app.utils.config_validator import dump_all_settings, get_settings_for_display
+    from app.utils.config_validator import dump_all_settings
+
     # Dump full settings to log for admin to see
     dump_all_settings()
-    
+
     # Return safe subset of settings for API response
     safe_settings = {
         "workdir": settings.workdir,
         "external_hostname": settings.external_hostname,
         "configured_services": {
-            "email": bool(getattr(settings, 'email_host', None)),
-            "s3": bool(getattr(settings, 's3_bucket_name', None)),
-            "dropbox": bool(getattr(settings, 'dropbox_refresh_token', None)),
-            "onedrive": bool(getattr(settings, 'onedrive_refresh_token', None)),
-            "nextcloud": bool(getattr(settings, 'nextcloud_upload_url', None)),
-            "sftp": bool(getattr(settings, 'sftp_host', None)),
-            "paperless": bool(getattr(settings, 'paperless_host', None)),
-            "google_drive": bool(getattr(settings, 'google_drive_credentials_json', None)),
-            "uptime_kuma": bool(getattr(settings, 'uptime_kuma_url', None)),
-            "auth": bool(getattr(settings, 'authentik_config_url', None)),
-            "openai": bool(getattr(settings, 'openai_api_key', None)),
-            "azure": bool(getattr(settings, 'azure_api_key', None) and getattr(settings, 'azure_endpoint', None)),
+            "email": bool(getattr(settings, "email_host", None)),
+            "s3": bool(getattr(settings, "s3_bucket_name", None)),
+            "dropbox": bool(getattr(settings, "dropbox_refresh_token", None)),
+            "onedrive": bool(getattr(settings, "onedrive_refresh_token", None)),
+            "nextcloud": bool(getattr(settings, "nextcloud_upload_url", None)),
+            "sftp": bool(getattr(settings, "sftp_host", None)),
+            "paperless": bool(getattr(settings, "paperless_host", None)),
+            "google_drive": bool(getattr(settings, "google_drive_credentials_json", None)),
+            "uptime_kuma": bool(getattr(settings, "uptime_kuma_url", None)),
+            "auth": bool(getattr(settings, "authentik_config_url", None)),
+            "openai": bool(getattr(settings, "openai_api_key", None)),
+            "azure": bool(getattr(settings, "azure_api_key", None) and getattr(settings, "azure_endpoint", None)),
         },
-        "imap_enabled": bool(getattr(settings, 'imap1_host', None) or getattr(settings, 'imap2_host', None)),
+        "imap_enabled": bool(getattr(settings, "imap1_host", None) or getattr(settings, "imap2_host", None)),
     }
-    
+
     return {
         "status": "success",
         "settings": safe_settings,
-        "message": "Full settings have been dumped to application logs"
+        "message": "Full settings have been dumped to application logs",
     }
 
+
 @router.post("/diagnostic/test-notification")
 @require_login
 async def test_notification(request: Request):
     # Add request_time to request.state
     import datetime
+
     request.state.request_time = datetime.datetime.utcnow().isoformat()
     """
     Send a test notification through all configured notification channels
     """
     from app.utils.notification import send_notification
-    
+
     try:
-        notification_urls = getattr(settings, 'notification_urls', [])
+        notification_urls = getattr(settings, "notification_urls", [])
         if not notification_urls:
             return {
                 "status": "warning",
-                "message": "No notification services configured. Add notification URLs to your configuration."
+                "message": "No notification services configured. Add notification URLs to your configuration.",
             }
-        
+
         # Send a test notification
         hostname = settings.external_hostname or "Document Processor"
         result = send_notification(
             title=f"Test Notification from {hostname}",
-            message=f"This is a test notification sent at {request.state.request_time}. If you're receiving this, notifications are working!",
+            message=(
+                f"This is a test notification sent at {request.state.request_time}. "
+                "If you're receiving this, notifications are working!"
+            ),
             notification_type="success",
-            tags=["test", "notification", "diagnostic"]
+            tags=["test", "notification", "diagnostic"],
         )
-        
+
         if result:
             logger.info("Test notification sent successfully")
             return {
                 "status": "success",
                 "message": f"Test notification sent successfully to {len(notification_urls)} service(s)",
-                "services_count": len(notification_urls)
+                "services_count": len(notification_urls),
             }
         else:
             logger.warning("Test notification send attempt returned False")
             return {
                 "status": "error",
-                "message": "Failed to send test notification. Check application logs for details."
+                "message": "Failed to send test notification. Check application logs for details.",
             }
-    
+
     except Exception as e:
         logger.exception(f"Error sending test notification: {e}")
-        return {
-            "status": "error",
-            "message": f"Error sending notification: {str(e)}"
-        }
+        return {"status": "error", "message": f"Error sending notification: {str(e)}"}