feat: US-001 — scaffold NeuralDesk Electron + React app

- electron-forge 7 + Vite plugin (vite-typescript template)
- React 19 + TypeScript 5 strict mode
- TanStack Router with file-based routing (4 routes: /, /timeline, /tasks, /projects)
- Tailwind CSS 3 + PostCSS with Figma design tokens (sidebar, primary, muted)
- Framer Motion, Lucide React, shadcn/ui utilities (cn, CVA, clsx, twMerge)
- AppShell layout: 240px sidebar with collapse toggle, active route highlighting
- Vite configs use .mts extension to avoid ESM/CJS conflict with electron-forge
- Full package build verified (linux x64)

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

tsconfig.json

@@ -0,0 +1,22 @@
+{
+  "compilerOptions": {
+    "target": "ESNext",
+    "module": "ESNext",
+    "moduleResolution": "bundler",
+    "lib": ["ESNext", "DOM", "DOM.Iterable"],
+    "jsx": "react-jsx",
+    "strict": true,
+    "noUncheckedIndexedAccess": true,
+    "allowJs": false,
+    "skipLibCheck": true,
+    "esModuleInterop": true,
+    "resolveJsonModule": true,
+    "sourceMap": true,
+    "baseUrl": ".",
+    "paths": {
+      "@/*": ["src/renderer/*"]
+    },
+    "outDir": "dist"
+  },
+  "include": ["src", "forge.config.ts", "forge.env.d.ts", "vite.*.config.ts", "vite.*.config.mts"]
+}