fix(browse): make browser cookie picker resilient

[fongryan]

Summary\n\n- extend one-time picker handoff to five minutes\n- carry target hostname into domain-aware profile selection\n- retry transient Chromium DB/keychain contention with bounded backoff\n- add opt-in post-import authentication verification without exposing cookie or identity values\n- add focused tests and browse/COOKIE-IMPORT.md\n\n## Verification\n\n- 53 focused cookie-picker/import/auth-verification tests pass\n- targeted Bun bundles compile where installed dependencies permit\n- full build remains blocked by pre-existing missing node_modules/xterm and sharp dependencies\n

[trunk-io]

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[fongryan]

/trunk merge

[trunk-io]

An error occurred while submitting your PR to the queue: Only users that are a part of this repo's Trunk organization or have write permissions to the repo can submit a PR to the queue

[fongryan]

/trunk merge

[trunk-io]

An error occurred while submitting your PR to the queue: Only users that are a part of this repo's Trunk organization or have write permissions to the repo can submit a PR to the queue

[fongryan]

Reliability follow-up evidence (commit 0f4f2fd):

• Focused cookie suite: 57 passed, 0 failed, 152 expectations across 4 cookie-picker/auth/import test files.
• Production build: bun run build passes after restoring the declared Bun dependencies.
• Added bounded retries for transient Chromium DB/keychain contention, exact/dot-boundary domain matching, retry-aware profile discovery, fail-closed post-import auth verification, route-level dependency injection tests, and refreshed generated browse docs.
• Full repository test run was attempted; unrelated pre-existing timeout/SIGPIPE failures remain in global discovery, developer profile, and gbrain detection tests. No cookie-picker test failed.
• git diff --check passes; lane is clean.

The PR is ready for maintainer merge. Direct upstream push is unavailable to this fork author, and Trunk queue submission requires repo write/Trunk membership.

[fongryan]

/trunk merge

[trunk-io]

An error occurred while submitting your PR to the queue: Only users that are a part of this repo's Trunk organization or have write permissions to the repo can submit a PR to the queue