ci: source release body from the annotated tag message

The release step created releases with no body. Read the tag's annotation
into RELEASE_NOTES.md and pass it via body_path so each release carries
purpose-written notes. Fetch full history so the annotated tag object is
available to the build.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitea/workflows/release.yml

@@ -10,6 +10,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
 
       - uses: actions/setup-go@v5
         with:
@@ -41,6 +43,9 @@ jobs:
           sha256sum "dist/${STAGE}.tar.gz" "dist/${STAGE}/weircon-random-proxy" > dist/SHA256SUMS
           ls -lh dist/
 
+      - name: Extract release notes from tag
+        run: git tag -l --format='%(contents)' "${{ github.ref_name }}" > RELEASE_NOTES.md
+
       - name: Upload release asset
         uses: https://gitea.com/actions/gitea-release-action@v1
         with:
@@ -48,6 +53,7 @@ jobs:
           server_url: ${{ github.server_url }}
           tag_name: ${{ github.ref_name }}
           name: ${{ github.ref_name }}
+          body_path: RELEASE_NOTES.md
           files: |
             dist/weircon-random-proxy-${{ github.ref_name }}-linux-amd64.tar.gz
             dist/weircon-random-proxy-${{ github.ref_name }}-linux-amd64/weircon-random-proxy