fix: consume repeated YouTube browser handoffs

[MyButtermilk]

Summary

• subscribe browser imports to search-string changes instead of pathname-only navigation
• preserve a pending handoff while an earlier YouTube start request is in flight
• add component regressions for an already-open /youtube route and deferred consumption

Installed failure evidence

• v0.5.91 accepted the redacted shell handoff and opened /youtube, but created no new YouTube job
• the exact v0.5.91 release was restored to draft without moving its immutable tag

Validation

• npm run check
• npm run lint
• npm test (98 library + 73 component tests)
• npm run build
• focused new component tests: 2 passed
• tests/test_frontend_type_gates.py: 104 passed
• Chrome extension contract: 3 passed

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: be5ba97d2e

ℹ️ About Codex in GitHub

Codex has been enabled to automatically review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

When you sign up for Codex through ChatGPT, Codex can also answer questions or update the PR, like "@codex address that feedback".

[chatgpt-codex-connector]

Parse the current search before consuming the handoff

When a second shell navigation arrives after this render captured request A but before the passive effect executes, window.location.search already contains request B while search still contains A. This line derives an empty query from stale A and the following replaceState overwrites B, so the newer handoff is never consumed or retained. Read and strip the current window.location.search inside the effect, using useSearch() only to trigger reruns.

AGENTS.md reference: AGENTS.md:L243-L247

Useful? React with 👍 / 👎.