fix: stop skipping GHCR publishes for docs-only pushes

[mrubens]

Problem

The Publish GHCR Images workflow skipped all build jobs for docs-only develop/main pushes. That skip is wrong in two ways:

1. It ships stale content. Since Ship apps/docs in the app image so setup docs render #754 the app image copies apps/docs into the image — the web server reads setup-flow docs from ../docs at request time — so a "docs-only" change produces a genuinely different app image. The skip predates that change. The classifier also treated every *.md/*.mdx in the repo as docs, even though some markdown (for example workflow SKILL.md sources) is runtime content.

2. It breaks immutable-tag consumers. A skipped push leaves the commit with no <channel>-<sha8> image tag. pnpm dev derives ghcr.io/roocodeinc/roomote-worker:develop-<first 8 chars of origin/develop> for hosted compute, so after a changelog-only push lands on develop (for example acab6738, where every build/publish job was skipped), Modal sandbox creation fails with an empty "Image build for im-... failed" error and every local task run fails to spawn until the next code push. Verified against the registry: develop-acab6738 returns 404 while develop-4a08f555 and the develop alias return 200.

Fix

Remove the docs-only skip entirely: delete the Classify changed paths step and the docs_only gates on deployment-acceptance, build, and create-github-release. Every develop/main push now builds and publishes, restoring the invariant that every branch commit has a published immutable tag and keeping shipped docs current.

Alternatives considered and dropped:

• Client-side registry check in pnpm dev (probe GHCR, walk back to the newest published tag): works, but adds machinery to every consumer and leaves the tag gap in place.
• Retagging the previous image under the new sha for docs-only pushes: fixes the tag gap cheaply, but publishes a stale app image under the new commit's tag, since docs-only changes do affect the app image (caught by review on an earlier revision of this PR).

Tradeoff: changelog-only and docs-only pushes now pay for a full image build. Those pushes are infrequent, and the previous behavior was silently shipping stale docs, so the skip was not a safe optimization to keep.

Validation

• Workflow YAML parses cleanly; the diff is a pure removal (1 insertion, 54 deletions).
• No docs_only references remain in the workflow.

[roomote-roomote]

No code issues found. See task

• .github/workflows/publish-ghcr.yml:408: Do not retag roomote-app for every docs_only push. The app Dockerfile copies apps/docs and builds the web app from it, so a change under apps/docs produces a new app image. This retag publishes the previous app image under the new commit tag and advances the channel alias, leaving the shipped setup-flow docs and docs assets stale. Build and publish the app image when apps/docs/** changes, or restrict this retag to paths that cannot affect it.

_{Reviewed 6a6203b}

[mrubens]

Good catch — confirmed: since #754 the app Dockerfile copies apps/docs into the image (the web server reads setup-flow docs from ../docs at request time), so retagging the previous app image under a docs-only commit would ship stale docs. Rather than restricting the retag, the PR now removes the docs-only skip entirely: the skip predates #754 and was already shipping stale docs by never publishing docs-only changes at all. Every develop/main push now builds and publishes.