Step 5 of the phase-2 App.tsx decomposition (#2129, under #2126): the two
sandbox bridge factories, the renderer handle, and the app-rendered
elicitation controller move out of App.tsx into a hook of their own.
Nearly a leaf — it reads the active client and the resource listing and
calls nothing back — so `getListedResourceMeta`, `publishDocument` and
`listedResourcesRef` become internal to the hook rather than App.tsx
locals. The hook is called where `resources` is derived, which is what
lets it own the latest-listing ref write too.
`sandboxUrl` and `initialConfigSettledRef` deliberately stay in App.tsx:
whether the sandbox exists decides whether the client advertises the
nested MCP Apps `elicitation` capability, and that is a
connection-lifecycle question rather than an Apps one.
Inert by construction: no behavior change, and the extraction is covered
100% on all four dimensions plus the existing `smoke:web:app` and
`smoke:web:elicit`, in both Chromium and Firefox.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013hzwzS8UvBsr4yZm7o7sev
Signed-off-by: cliffhall <cliff@futurescale.com>
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