fix: ignore Cursor replayed turn output

[tarik02]

Summary

• Ignore turn-output runtime events that arrive without the active turn id while a turn is running.
• Remember item ids from skipped no-turn replay events so their follow-up completion under the active turn is skipped too.
• Add a regression test for Cursor ACP replay after backend restart: old assistant segment is replayed without turnId, then the new turn continues with later segments.

Upstream check

• Checked latest upstream/main; it does not add a replay guard for this case.
• Upstream currently uses provider item ids for assistant messages in ProviderRuntimeIngestion, which does not mitigate Cursor segment replay/reuse. This fork keeps turn-scoped assistant ids and adds the replay guard.

Validation

• ./node_modules/.bin/vp test run apps/server/src/orchestration/Layers/ProviderRuntimeIngestion.test.ts -t "ignores cursor assistant item replay"
• ./node_modules/.bin/vp test run apps/server/src/orchestration/Layers/ProviderRuntimeIngestion.test.ts
• ./node_modules/.bin/vp check --fix && ./node_modules/.bin/vp check
• ./node_modules/.bin/vp run typecheck