Add desktop (Electron) packaging and release distribution (#1147)

* Add desktop packaging workflow

* Add desktop package homepage

* Fix desktop default credential prompt

* Suppress default credential prompt on desktop

* Publish desktop artifacts on release; reduce CI to PR smoke test

Add desktop-release.yml triggered on release publish (mirroring
docker-publish.yml) to build all platforms and upload .dmg/.exe/
.AppImage/.deb to the GitHub Release.

Trim build.yml desktop job to a PR-only Linux x64 smoke test, since
release artifacts are now produced by desktop-release.yml. This drops
per-push and macOS/Windows packaging from regular CI.

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

* Fix desktop Hermes data home on Windows

---------

Co-authored-by: xingzhi <chuzihao.czh@alibaba-inc.com>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

packages/desktop/README.md

@@ -0,0 +1,31 @@
+# Hermes Desktop
+
+Electron desktop distribution for Hermes Web UI.
+
+## Data directories
+
+Hermes Agent data is stored in the same platform-specific location as native
+Hermes installs:
+
+- Windows: `%LOCALAPPDATA%\hermes` (falls back to `%APPDATA%\hermes`)
+- macOS/Linux: `~/.hermes`
+
+The desktop wrapper's own Web UI state is stored separately in
+`~/.hermes-web-ui` unless `HERMES_WEB_UI_HOME` is set.
+
+## China mirror environment
+
+These mirrors are optional and are not required in CI:
+
+```sh
+export NPM_CONFIG_REGISTRY=https://registry.npmmirror.com
+export ELECTRON_MIRROR=https://npmmirror.com/mirrors/electron/
+export ELECTRON_BUILDER_BINARIES_MIRROR=https://npmmirror.com/mirrors/electron-builder-binaries/
+```
+
+If GitHub release downloads are slow, `fetch-python.mjs` can also use a compatible
+python-build-standalone release mirror:
+
+```sh
+export PBS_BASE_URL=https://github.com/astral-sh/python-build-standalone/releases/download
+```