ci: trigger release build on published release instead of tag push

Both workflows now run on `release: published` and attach the built
archives to the release the user creates, rather than pushing a tag and
having the workflow create the release. Tag comes from the release event;
GitHub no longer regenerates release notes. Docs updated accordingly.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.forgejo/workflows/release.yml

@@ -11,9 +11,8 @@ name: Release
 # Settings -> Actions -> Secrets. Without it the build still runs; only the
 # upload step is skipped.
 on:
-  push:
-    tags:
-      - "v*"
+  release:
+    types: [published]
   workflow_dispatch:
 
 jobs:
@@ -71,8 +70,9 @@ jobs:
           rm -rf /var/lib/apt/lists/*
 
       - name: Derive version
-        # On a tag push, strip the leading "v" so artifact names and the injected
-        # app version match the release tag.
+        # On a release, strip the leading "v" so artifact names and the injected
+        # app version match the release tag (the release event still sets
+        # GITHUB_REF_TYPE=tag / GITHUB_REF_NAME=<tag>).
         id: version
         run: |
           if [ "${GITHUB_REF_TYPE:-}" = "tag" ]; then
@@ -93,14 +93,16 @@ jobs:
           mkdir -p dist/release
           cp dist/linux/*.tar.gz dist/windows/*.zip dist/release/
 
-      - name: Publish release
-        if: ${{ startsWith(github.ref, 'refs/tags/') }}
+      - name: Attach assets to release
+        # Only runs for the release event; the release already exists, so this
+        # uploads the built archives to it. Skipped on workflow_dispatch.
+        if: ${{ github.event_name == 'release' }}
         uses: https://code.forgejo.org/actions/forgejo-release@v2
         with:
           direction: upload
           url: https://codeberg.org
           repo: ${{ github.repository }}
-          tag: ${{ github.ref_name }}
+          tag: ${{ github.event.release.tag_name }}
           release-dir: dist/release
           token: ${{ secrets.RELEASE_TOKEN }}
           override: true