[Fix] Fast mode cannot manage custom automations

[roomote-roomote]

​Opened on behalf of @mrubens. Follow up by mentioning @roomote-roomote or in the web UI.

What changed

• Authorize custom automation management from the trusted Fast parent session binding instead of inferring caller identity from OpenCode's optional agent label.
• Keep custom automation management blocked for advisor, judge, and other delegated subagent sessions.
• Cover the reported manage_custom_automations list call through the parent's integration_call path with a non-empty agent label.

Why this change was made

OpenCode includes an agent label on parent tool calls as well as delegated calls, so treating any labeled call as a subagent incorrectly rejected the Fast parent itself.

Impact

Fast conversations can list and manage custom automations through the Roomote deployment MCP again, without expanding the capability to delegated subagents.

[roomote-community]

No code issues found. See task

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