Add an accordion under the Built-in provider tab describing the runtime
catalog refresh from the Copilot `/models` endpoint and the
`plugins.entries.github-copilot.config.discovery.enabled = false` opt-out
for offline / air-gapped scenarios. Pairs with the
`fetchCopilotModelCatalog` change so users know what the new behavior
is and how to disable it if needed.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>