Only create releases for tags pointing at master

Guard the Create Gitea release step: fetch origin/master and compare with
the tagged commit; if the tag is not on master's tip, skip release creation
instead of publishing a release for a feature/dev branch.

.gitea/workflows/build-apk.yml

@@ -94,6 +94,13 @@ jobs:
           GITHUB_TOKEN: ${{ github.token }}
         run: |
           set -eux
+          # Releases only for tags that point at the master branch tip —
+          # a tag pushed to a feature/dev branch never creates a release.
+          git fetch origin master
+          if [ "$(git rev-parse HEAD)" != "$(git rev-parse FETCH_HEAD)" ]; then
+            echo "Tag ${GITHUB_REF_NAME} does not point to master — skipping release creation"
+            exit 0
+          fi
           TAG=${GITHUB_REF_NAME}
           API="${{ github.api_url }}/repos/${GITHUB_REPOSITORY}"
           REL=$(curl -s -X POST "$API/releases" \