fix(archive): tolerate task pin sync failures

[richardsolomou]

Problem

Task archiving fails when task pin reads or updates fail, affecting both cloud and worktree tasks. Pin synchronization is ancillary and should not prevent an archive from completing.

Changes

I made pin reads and writes best-effort during archive orchestration. When pin state cannot be read, archiving leaves it unchanged so a later archive failure cannot accidentally unpin the task. Failed rollback pin writes are logged without replacing the original archive error.

How did you test this?

• pnpm --dir packages/core exec vitest run src/archive/archiveOrchestration.test.ts src/sessions/sessionServiceStopCloudRun.test.ts
• pnpm exec biome check packages/core/src/archive/archiveOrchestration.ts packages/core/src/archive/archiveOrchestration.test.ts
• pnpm --filter @posthog/core... build
• pnpm --filter @posthog/core typecheck

Automatic notifications

• Publish to changelog?
• Alert Sales and Marketing teams?

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Created with PostHog Code

[trunk-io]

😎 Merged directly without going through the merge queue, as the queue was empty and the PR was up to date with the target branch - details.

[github-actions]

React Doctor found no issues in the changed files. 🎉

_{Reviewed by React Doctor for commit 4eae17a.}

[greptile-apps]

Prompt To Fix All With AI

### Issue 1
packages/core/src/archive/archiveOrchestration.ts:70-75
**Failed pin read breaks rollback**

When reading a pinned task's state fails, `wasPinned` remains false even though the subsequent unpin can succeed. If the archive then fails, rollback skips restoring the pin, leaving the task incorrectly unpinned despite the failed archive.

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For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

_{Reviews (1): Last reviewed commit: "Fix task archiving when pin sync fails" | Re-trigger Greptile}

[posthog]

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