Council member tasks were launched via BackgroundManager but lacked the
ctx.metadata() call that links background sessions to the tool call in
the OpenCode TUI. Users couldn't click to inspect individual member outputs.
- Add session-waiter.ts to poll for session creation on launched tasks
- Call ctx.metadata() for each council member with sessionId linkage
- Matches the pattern used by delegate-task/background-task.ts
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
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