fix: use uuid field instead of pk for Authentik user sync

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/auth/service.py

@@ -396,13 +396,13 @@ class AuthService:
                 for auth_user in authentik_users:
                     try:
                         # Skip service accounts and inactive users
-                        if auth_user.get("type") == "service_account":
+                        if auth_user.get("type") in ("service_account", "internal_service_account"):
                             continue
                         if not auth_user.get("is_active", True):
                             continue
 
                         # Extract user data from Authentik
-                        authentik_id = uuid.UUID(auth_user["pk"])
+                        authentik_id = uuid.UUID(auth_user["uuid"])
                         email = auth_user.get("email") or f"{auth_user['username']}@local"
                         name = auth_user.get("name") or auth_user.get("username", "Unknown")
                         avatar_url = auth_user.get("avatar")