fix: load models before resolving automation model defaults (#30379)

Automations lost their model's tool bindings (including MCP servers), default features such as web search, default filters and terminal on the first run after a restart. The model then answered that it had no tools. Later runs and a manual Regenerate worked. Automations on the base models cache were not affected.

The run read the model from app.state.MODELS before anything had loaded it. After a restart or a connection settings save, that cache stays empty until a browser loads the model list or a chat completion runs. The completion runs only after the automation has already built its request.

execute_automation now loads the models when the cache is empty, using the same guard chat_completion uses, before either the chat or the channel target reads it. This also fixes channel automations showing the raw model ID in place of the model name on a cold cache.

Verified end to end on a restarted instance with a mock upstream: before, both chat and channel runs reached the pipeline without tool_ids or features. After, both carry the model's tools and web search, and the upstream receives the tool.

Fixes #27694

backend/open_webui/utils/automations.py

@@ -37,6 +37,7 @@ from open_webui.models.messages import MessageForm
 from open_webui.models.users import Users
 from open_webui.utils.auth import create_token
 from open_webui.utils.misc import parse_duration
+from open_webui.utils.models import get_all_models
 from open_webui.utils.recurrence import (
     _resolve_tz,
     next_n_runs_ns,
@@ -390,6 +391,9 @@ async def execute_automation(app, automation: AutomationModel) -> None:
             expires_delta=expires_delta or timedelta(hours=1),
         )
 
+        if not app.state.MODELS:
+            await get_all_models(_build_request(app, token=token), user=user)
+
         target = automation.data.get('target') or {}
         if target.get('type') == 'channel':
             await _execute_channel_automation(app, automation, user, prompt, model_id, token)