Sprint 17.F — Retry interactive browser QA

[maruson08]

Goal

Attempt to close the outstanding interactive browser QA debt.

Acceptance criteria

• If browser control works, test JPEG/PNG/WebP metadata inspection, decoded/opaque/partial states, Privacy Clean verification, output usability, themes, locales, narrow width, keyboard use, Network panel, and representative broader v2 smoke paths.
• If startup fails, record the environment, attempt, exact error, affected checks, and BLOCKED status.
• Never report blocked browser QA as PASS.

[maruson08]

Completed in PR #44. Interactive browser QA was retried and BLOCKED before navigation by: windows sandbox failed: helper_unknown_error: apply deny-read ACLs. Manual QA remains open in docs/v2-release-qa.md; no visual pass is claimed.