Vouch request: fix duplicate final answers after continuation turns (#4840)

[mastertyko]

Hi @can1357 — requesting a vouch to contribute.

What I'd like to contribute: a ready fix for #4840, where the coding agent can show duplicate final answers after agent-authored continuation turns.

I investigated the issue and prepared a minimal candidate fix on my fork:

https://github.com/mastertyko/oh-my-pi/tree/fix/duplicate-summary-continuations

The fix prevents autolearn/advisor/compaction follow-up turns from re-emitting the same final answer after the original user-visible turn has already completed.

Testing performed locally:

• bun test packages/coding-agent/test/autolearn-controller.test.ts packages/coding-agent/test/agent-session-advisor-suppression.test.ts packages/coding-agent/test/agent-session-auto-compaction-queue.test.ts
• bun run check:types

I'll open the PR once vouched. Thanks.