chore: sync final dev fix into v0.9.10

[numnx]

What changed

• Merge the green dev head into release/v0.9.10.
• Include the host-worktree ownership fix from fix: canonicalize host worktree ownership #3143.
• Preserve the release-only package version 0.9.10.

Verification

• The sync branch contains both current dev and release/v0.9.10 as ancestors.
• Its tree differs from dev only by package.json retaining version 0.9.10.
• The source fix passed backend coverage, dashboard tests, package smoke, docs smoke, and Linux, Windows, and macOS orchestration lanes on fix: canonicalize host worktree ownership #3143.

Risk and rollback

Low risk. This is an integration-only merge with no conflict resolution. Rollback is reverting this merge commit on the release branch.