macos: enable running lan-mouse on macos (#42)

* macos: initial support

- adapted conditional compilation
- moved lan-mouse socket to ~/Library/Caches/lan-mouse-socket.sock instead of XDG_RUNTIME_DIR
- support for mouse input emulation
TODO: Keycode translation, input capture

.github/workflows/rust.yml

@@ -46,3 +46,19 @@ jobs:
       with:
         name: lan-mouse-windows
         path: target/debug/lan-mouse.exe
+
+  build-macos:
+    runs-on: macos-latest
+    steps:
+    - uses: actions/checkout@v3
+    - name: install dependencies
+      run: brew install gtk4 libadwaita
+    - name: Build
+      run: cargo build --verbose
+    - name: Run tests
+      run: cargo test --verbose
+    - name: Upload build artifact
+      uses: actions/upload-artifact@v3
+      with:
+        name: lan-mouse-macos
+        path: target/debug/lan-mouse