Convert web app to Electron desktop application

- Add Electron main process with developer tools support
- Create preload script for secure context bridge
- Configure electron-builder for packaging
- Update Vite config for Electron compatibility (base: './')
- Add environment variable support for API host configuration
- Fix i18n to use relative paths for Electron file protocol
- Restore multi-port backend architecture (8081-8085)
- Add enhanced backend startup script with port checking
- Update package.json with Electron dependencies and build scripts

🤖 Generated with [Claude Code](https://claude.ai/code)

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

electron-builder.json

@@ -0,0 +1,84 @@
+{
+  "appId": "com.termix.app",
+  "productName": "Termix",
+  "directories": {
+    "output": "release",
+    "buildResources": "build"
+  },
+  "files": [
+    "dist/**/*",
+    "electron/main-simple.cjs",
+    "electron/preload-simple.cjs",
+    "public/icon.*",
+    "package.json"
+  ],
+  "asar": true,
+  "mac": {
+    "category": "public.app-category.developer-tools",
+    "icon": "public/icon.icns",
+    "hardenedRuntime": true,
+    "gatekeeperAssess": false,
+    "entitlements": "build/entitlements.mac.plist",
+    "entitlementsInherit": "build/entitlements.mac.plist",
+    "target": [
+      {
+        "target": "dmg",
+        "arch": ["x64", "arm64"]
+      },
+      {
+        "target": "zip",
+        "arch": ["x64", "arm64"]
+      }
+    ]
+  },
+  "win": {
+    "icon": "public/icon.ico",
+    "target": [
+      {
+        "target": "nsis",
+        "arch": ["x64", "ia32"]
+      },
+      {
+        "target": "portable",
+        "arch": ["x64"]
+      }
+    ]
+  },
+  "linux": {
+    "category": "Development",
+    "target": [
+      {
+        "target": "AppImage",
+        "arch": ["x64"]
+      }
+    ]
+  },
+  "nsis": {
+    "oneClick": false,
+    "perMachine": false,
+    "allowToChangeInstallationDirectory": true,
+    "deleteAppDataOnUninstall": false,
+    "createDesktopShortcut": true,
+    "createStartMenuShortcut": true
+  },
+  "dmg": {
+    "contents": [
+      {
+        "x": 410,
+        "y": 150,
+        "type": "link",
+        "path": "/Applications"
+      },
+      {
+        "x": 130,
+        "y": 150,
+        "type": "file"
+      }
+    ]
+  },
+  "publish": {
+    "provider": "github",
+    "owner": "LukeGus",
+    "repo": "Termix"
+  }
+}