feat(web): add toggleable confirmation before unpinning a thread - #7313

💭 I'm checking useThreadActions.ts to see if it involves Effect service patterns like settlePromise or AsyncResult, since the diff mostly touches React hooks and a contracts schema rather than actual Effect service code, so I want to confirm whether the Effect conventions check even applies here.

1. browse_code — apps/web/src/hooks/useThreadActions.ts

2. browse_code — apps/web/src/hooks/useThreadActions.ts

💭 This is React code, not Effect services, so the service convention check doesn't really apply here. The imports follow the existing namespace subpath pattern, and I don't see this PR creating, moving, or refactoring an Effect service, so there's nothing to flag on that front. The contracts/settings.ts change just adds a schema field, which looks fine, and requestThreadUnpinConfirmation doesn't introduce any new error classes. I'll double check the import style near line 173 in settings.ts for consolidated named imports from "effect".

3. browse_code — packages/contracts/src/settings.ts

💭 Everything checks out cleanly against the Effect service conventions. There's a tension between the instruction to output exactly "All clear" and the requirement to return structured JSON, so I'll resolve it by putting "All clear" into the summary field while keeping the title concise and marking the state as success.