ci: only run on branch pushes; drop bump-script emerge; repoint vendor tags

- ci.yaml: filter the push trigger to branches. An unfiltered `push` also
  fired for every tag ref, including the vendor-release tags the bump script
  creates via the API.
- bump-version.sh: remove the pkgcheck/emerge/--version validation before
  push. The branch push triggers CI, which runs the same checks and, unlike
  the script's local copy, fetches the real release asset. The PR body now
  asks for green CI instead of claiming the build passed in the bump job.
- vendor-tags.yaml: new workflow on pushes to master touching dev-util/**.
  The vendor release is created before the bump commit exists (and PRs are
  squash-merged), so its tag pointed at an arbitrary master commit. This
  force-updates each vendor tag whose ebuild is in the tree to the master
  commit that added that ebuild. Tags are only ever updated, never deleted,
  since deleting a release's tag deletes the release and its assets.
- CLAUDE.md: document both changes.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

.gitea/workflows/ci.yaml

@@ -1,5 +1,10 @@
 name: CI
-on: [push]
+# Restrict to branch pushes: an unfiltered `push` also fires for tag refs,
+# including the vendor-release tags the bump script creates via the API.
+on:
+  push:
+    branches:
+      - '**'
 
 jobs:
   # Lint gate: runs on the plain Docker-backend runner (not the Gentoo

.gitea/workflows/vendor-tags.yaml

@@ -0,0 +1,43 @@
+name: Vendor tags
+# The bump script creates the `${PN}-${ver}-vendor` release (which hosts the
+# vendor tarball) *before* the bump commit exists, so its tag can only point at
+# whatever master was at the time. The PR is then squash/rebase-merged, so the
+# branch commit never lands on master either. This job re-points each vendor
+# tag at the master commit that introduced that version's ebuild. It is
+# idempotent: a tag already on the right commit is left alone.
+#
+# Only ever force-*update* a tag here. Deleting a release's tag makes Gitea
+# delete the release and its assets, which would break the ebuild's SRC_URI.
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - 'dev-util/**'
+
+jobs:
+  repoint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Point vendor tags at their bump commits
+        run: |
+          set -euo pipefail
+          git fetch --tags --force origin
+          for ebuild in dev-util/gitea-runner/gitea-runner-*.ebuild; do
+            ver=${ebuild##*/gitea-runner-}; ver=${ver%.ebuild}
+            tag="gitea-runner-${ver}-vendor"
+            if ! cur=$(git rev-parse --verify -q "refs/tags/${tag}^{commit}"); then
+              echo "${tag}: no such tag, skipping"; continue
+            fi
+            # git mv shows up as an addition of the new path (no --follow).
+            target=$(git log --diff-filter=A --format=%H -1 -- "$ebuild")
+            if [ "$cur" = "$target" ]; then
+              echo "${tag}: already at ${target}"; continue
+            fi
+            echo "${tag}: ${cur} -> ${target}"
+            git push --force origin "${target}:refs/tags/${tag}"
+          done