feat(electron): scaffold electron-vite project structure

Initialize Wave 1 Electron integration with:
- electron v40.6.1, electron-vite v5.0.0, electron-builder v26.8.1
- Main entry point: electron/main/index.ts with app:// protocol registration
- Preload placeholder: electron/preload/index.ts for Wave 2 IPC
- electron.vite.config.ts with unified renderer chunk splitting strategy
- tsconfig.electron.json with ESNext module support
- Updated package.json with electron dependencies and scripts:
  - electron:dev, electron:build, electron:preview
- All original scripts (dev, build, test, etc) remain unchanged
- TypeScript compilation verified: tsc --noEmit passes
- Ready for Wave 2: IPC bridge and contextBridge exposure

dashboard/tsconfig.electron.json

@@ -0,0 +1,36 @@
+{
+  "compilerOptions": {
+    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.electron.tsbuildinfo",
+    "target": "ES2020",
+    "useDefineForClassFields": true,
+    "lib": ["ES2020"],
+    "module": "ESNext",
+    "moduleResolution": "bundler",
+    "types": ["electron"],
+    "skipLibCheck": true,
+
+    /* Module resolution */
+    "allowImportingTsExtensions": true,
+    "verbatimModuleSyntax": false,
+    "moduleDetection": "force",
+    "noEmit": true,
+
+    /* Path aliases */
+    "baseUrl": ".",
+    "paths": {
+      "@/*": ["./src/*"]
+    },
+
+    /* Linting */
+    "strict": true,
+    "allowSyntheticDefaultImports": true,
+    "esModuleInterop": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "erasableSyntaxOnly": true,
+    "noFallthroughCasesInSwitch": true,
+    "noUncheckedSideEffectImports": true,
+    "skipLibCheck": true
+  },
+  "include": ["electron/**/*"]
+}