build_mac: auto-publish DMG to latest GitHub Release after build

On every successful Mac build, the DMG is now automatically uploaded
to the latest release so anyone can download it directly from the
Releases page without needing a GitHub account or Actions access.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: sprawf

.github/workflows/build_mac.yml

@@ -127,10 +127,21 @@ jobs:
             "Hotkeys-mac.dmg" \
             "dmg_src/"
 
-      # ── 9. Upload DMG as workflow artifact ───────────────────────────────────
-      - name: Upload DMG
+      # ── 9. Upload DMG as workflow artifact (90-day cache) ────────────────────
+      - name: Upload DMG artifact
         uses: actions/upload-artifact@v4
         with:
           name: Hotkeys-mac
           path: Hotkeys-mac.dmg
           retention-days: 90
+
+      # ── 10. Publish to latest GitHub Release ─────────────────────────────────
+      - name: Publish to GitHub Release
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          # Find the latest release tag and attach the DMG to it
+          LATEST_TAG=$(gh release list --limit 1 --json tagName --jq '.[0].tagName')
+          echo "Publishing to release: $LATEST_TAG"
+          gh release upload "$LATEST_TAG" Hotkeys-mac.dmg --clobber
+          echo "Published: $(gh release view $LATEST_TAG --json assets --jq '.assets[].name')"