fix: resolve 21 mypy type errors across backend modules

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

backend/app/api/v1/endpoints/auth.py

@@ -153,13 +153,13 @@ async def login(
 
     # Domain restriction — superusers always bypass
     if not user.is_superuser:
-        _check_domain_allowed(user.email)
+        _check_domain_allowed(str(user.email))
 
     # Update last login
     user.last_login_at = datetime.now(timezone.utc)  # type: ignore[assignment]
 
     # Auto-promote to superuser if this is the configured admin email
-    if not user.is_superuser and _is_admin_email(user.email):
+    if not user.is_superuser and _is_admin_email(str(user.email)):
         user.is_superuser = True  # type: ignore[assignment]
         logger.info(f"Auto-promoted admin user: {user.email}")
 

backend/app/api/v1/endpoints/mail_accounts.py

@@ -75,7 +75,7 @@ async def create_mail_account(
                 "pro": settings.TIER_PRO_MAX_ACCOUNTS,
                 "enterprise": settings.TIER_ENTERPRISE_MAX_ACCOUNTS,
             }
-            max_accounts = tier_limits.get(current_user.subscription_tier.value, 1)
+            max_accounts = tier_limits.get(current_user.subscription_tier.value, 1)  # type: ignore[assignment]
 
         if len(existing_accounts) >= max_accounts:
             raise HTTPException(
@@ -320,7 +320,7 @@ async def test_existing_mail_connection(
         )
 
     try:
-        password = decrypt_credential(account.encrypted_password)
+        password = decrypt_credential(str(account.encrypted_password))
     except Exception:
         raise HTTPException(
             status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,

backend/app/api/v1/endpoints/providers.py

@@ -266,7 +266,7 @@ async def save_gmail_credential(
             gmail_email=credential_in.gmail_email,
             encrypted_access_token=encrypted_access,
             encrypted_refresh_token=encrypted_refresh,
-            scopes=build_gmail_credential_scopes(),
+            scopes=build_gmail_credential_scopes(granted_scopes=[]),
             is_valid=True,
             last_verified_at=datetime.now(timezone.utc),
         )