Startup policy and hook/host warnings persist with isolated configuration on 1.0.109 and 1.0.110-3 #5431

Reproduction

On Windows x64, both stable 1.0.109 and official prerelease 1.0.110-3 emit these startup warnings:

`permissions.model` has an unsupported or malformed value and was ignored.
Failed to reload managed hooks after enabling managed settings: no hook session for session id [omitted]
event was not delivered to its registered session host: no session host is registered for session [omitted]

Each build was run once with a separate, fresh COPILOT_HOME and no copied user configuration. The runs used --no-auto-update, --no-custom-instructions, an empty --available-tools selection, and gpt-6-astra with max effort and long_context. Existing authentication was used; no credentials are included here.

Both one-turn synthetic prompts returned the requested response and recorded gpt-6-astra usage. Both reproduced the ignored model-policy warning and the early hook/session-host warnings. These are bounded observations, not proof that every startup fails or that hooks remain broken after initialization.

Expected behavior

Valid server policy should be interpreted consistently with its schema. Hook reload and host delivery should occur once their session infrastructure exists; if an early attempt cannot run, needed work should be retried after initialization rather than silently lost.

Please clarify the accepted permissions.model schema and whether these initialization warnings represent skipped work. Disabling managed policy, hooks, or remote features is not a suitable fix.

Related startup/resume report: #5341. This reproduction does not establish that the same hang occurs.