fix(ci): anchor the release-skip marker to a trailer, and test it

The tagger searched the entire commit message for a bracketed marker as a
substring. The commit that introduced the manifest-bump step described that
marker in its own body — so the tagger read its own documentation as an
instruction and skipped the release. Run 15 reported success with no tag, no
manifest bump and no error. Same failure family as everything else in this
sweep: the wrong thing happened silently.

The rule is now a git trailer matched anchored to its own line, consistent
with Bump-Type, and it lives in bin/should-skip-release rather than untested
inside YAML. tests/release_skip_test.sh pins six cases, including the exact
regression: a message that spells the marker out in prose must still tag.

A marker you cannot mention without triggering is a footgun, not a mechanism.

Bump-Type: patch

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BeAp5LTscnz2W7Ubt4eJ6m

.gitea/workflows/release.yml

@@ -30,8 +30,10 @@ jobs:
         run: |
           set -euo pipefail
           last_commit=$(git log -1 --pretty=%B)
-          if printf '%s' "$last_commit" | grep -qi '\[skip-release\]'; then
+          # Delegated to bin/should-skip-release so the rule is covered by
-            echo "skipping — commit marked [skip-release]"
+          # tests/release_skip_test.sh rather than living untested in YAML.
+          if printf '%s\n' "$last_commit" | sh bin/should-skip-release; then
+            echo "skipping — commit carries the Skip-Release trailer"
             echo "skip=true" >> "$GITHUB_OUTPUT"
             exit 0
           fi
@@ -73,8 +75,8 @@ jobs:
           if [ "$current" != "$version" ]; then
             sed -i "s/\"version\"[[:space:]]*:[[:space:]]*\"$current\"/\"version\": \"$version\"/" "$manifest"
             git add "$manifest"
-            # [skip-release] stops this push from re-triggering the tagger.
+            # The trailer below stops this push from re-triggering the tagger.
-            git commit -m "chore(release): plugin.json version $version [skip-release]"
+            git commit -m "chore(release): plugin.json version $version" -m "Skip-Release: true"
             git push origin HEAD:main
             echo "bumped $manifest to $version"
           fi

bin/should-skip-release

@@ -0,0 +1,25 @@
+#!/bin/sh
+# should-skip-release — reads a commit message on stdin. Exits 0 when the
+# release tagger should skip this commit, 1 when it should tag.
+#
+# Skipping is opt-in via a git trailer:
+#
+#   Skip-Release: true
+#
+# It is a TRAILER, matched anchored to its own line, deliberately. The first
+# version searched the whole message for a bracketed marker as a substring,
+# and the very commit that introduced the manifest-bump step described that
+# marker in its body — so the tagger read its own documentation as an
+# instruction and skipped the release. Success, no tag, no bump, no error
+# (run 15, 2026-08-23). A marker you cannot mention without triggering is a
+# footgun, not a mechanism.
+
+set -u
+
+msg=$(cat)
+
+if printf '%s\n' "$msg" | grep -qiE '^[[:space:]]*Skip-Release:[[:space:]]*true[[:space:]]*$'; then
+  exit 0
+fi
+
+exit 1

tests/release_skip_test.sh

@@ -0,0 +1,61 @@
+#!/bin/sh
+# Tests for bin/should-skip-release.
+#
+# The regression these exist for: an unanchored substring match let a commit
+# that merely *described* the skip marker skip its own release.
+
+set -u
+
+ROOT=$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)
+SUT="$ROOT/bin/should-skip-release"
+
+pass=0
+fail=0
+
+if [ ! -f "$SUT" ]; then
+  printf 'FAIL: %s does not exist\n' "$SUT"
+  exit 1
+fi
+
+# expect <skip|tag> <label> <<message on stdin>>
+expect() {
+  _want=$1
+  _label=$2
+  _msg=$3
+  printf '%s\n' "$_msg" | sh "$SUT"
+  _rc=$?
+  if [ "$_want" = skip ]; then _wrc=0; else _wrc=1; fi
+  if [ "$_rc" -eq "$_wrc" ]; then
+    pass=$((pass + 1)); printf '  ok   %s\n' "$_label"
+  else
+    fail=$((fail + 1)); printf '  FAIL %s (want %s, rc=%s)\n' "$_label" "$_want" "$_rc"
+  fi
+}
+
+expect skip 'trailer on its own line' 'chore(release): bump
+
+Skip-Release: true'
+
+expect skip 'trailer, case-insensitive' 'chore: x
+
+skip-release: TRUE'
+
+expect tag 'ordinary commit' 'feat: add a thing
+
+Bump-Type: minor'
+
+# --- the actual regression -------------------------------------------------
+expect tag 'prose MENTIONING the marker must still tag' 'docs+ci: document the release flow
+
+CI commits the manifest bump with a Skip-Release: true trailer so it does
+not re-trigger the tagger. The old [skip-release] marker was a substring
+match, which is exactly why this commit would have skipped itself.
+
+Bump-Type: patch'
+
+expect tag 'legacy bracketed marker no longer skips' 'chore: something [skip-release]'
+
+expect tag 'empty message' ''
+
+printf '\nrelease_skip: %d passed, %d failed\n' "$pass" "$fail"
+[ "$fail" -eq 0 ]