Fix release.sh pushing to a remote that does not exist

--push ran `git push origin HEAD`, but this repo's only remote is named
forgejo — so the flag failed after the script had already committed and
tagged, leaving the release half-done. Resolve the remote instead:
prefer forgejo, fall back to origin, else use the only remote present,
and fail with a clear message if there is none.

Also corrects the header comment, which claimed the script does not build
the APK and pointed at --gh / gh CLI. Forgejo CI builds the APK on every
branch push and attaches it to a Forgejo release on a v* tag push, which
is what Obtainium tracks. --gh is a leftover from the GitHub era.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

scripts/release.sh

@@ -18,9 +18,12 @@
 # It does NOT:
 #   - Build the Docker image (run `docker compose build`/`up -d` yourself
 #     or wire it to a deploy script / CI hook)
-#   - Build the Android APK (run `cd mobile/android && ./gradlew ...`
-#     yourself). This script just marks the version so the build tags
-#     correctly.
+#   - Build the Android APK itself. Forgejo CI does that
+#     (.forgejo/workflows/android-apk.yml): any branch push builds a signed
+#     APK as a 30-day workflow artifact, and a v* tag push additionally
+#     attaches it to a Forgejo release, which is what Obtainium tracks for
+#     updates. So --push is normally all you need; --gh is a leftover from
+#     the GitHub era and is not how releases are published here.
 # ============================================================
 
 set -euo pipefail
@@ -90,9 +93,25 @@ git tag -a "v${VERSION}" -m "Release v${VERSION}"
 echo "    tagged v${VERSION}"
 
 if $PUSH; then
-  git push origin HEAD
-  git push origin "v${VERSION}"
-  echo "    pushed to origin"
+  # This repo's remote is "forgejo", not "origin". Prefer forgejo, fall back
+  # to origin, otherwise use the only remote there is — so this keeps working
+  # if the remote is ever renamed. Pushing the tag is what makes CI attach the
+  # signed APK to a Forgejo release for Obtainium; the branch push alone only
+  # builds it as a 30-day workflow artifact.
+  REMOTE=""
+  for candidate in forgejo origin; do
+    if git remote get-url "$candidate" >/dev/null 2>&1; then REMOTE="$candidate"; break; fi
+  done
+  if [[ -z "$REMOTE" ]]; then
+    REMOTE=$(git remote | head -1)
+  fi
+  if [[ -z "$REMOTE" ]]; then
+    echo "ERROR: no git remote configured — cannot push. Commit and tag are still local." >&2
+    exit 1
+  fi
+  git push "$REMOTE" HEAD
+  git push "$REMOTE" "v${VERSION}"
+  echo "    pushed to $REMOTE"
 fi
 
 if $DO_RELEASE; then