Fix interrupted release recovery

[selfcontained]

Summary

• resume an untagged package version after a release fails instead of bumping again
• keep the browser extension manifest version synchronized during version bumps
• repair the pending v0.29.0 manifest version

Root cause

The v0.29.0 prepare job pushed its release commit before verification. The browser extension package version was bumped, but public/manifest.json remained at v0.28.4, so verification failed before the tag and GitHub release were created. A fresh run would otherwise bump the already-prepared version to v0.29.1.

Validation

• pnpm run check
• pnpm --filter @dispatch/browser-extension test (51 passed)
• pnpm run test:e2e (168 passed, 13 skipped)
• Prettier and git diff --check
• recovery sanity check selects v0.29.0 with latest tag v0.28.5