feat: scaffold Tauri v2 + React + TS with all dependencies

- Tauri v2 with React 19 + TypeScript + Vite 7
- Tauri plugins: fs, dialog, shell (registered in lib.rs)
- Filesystem permissions scoped to $APPDATA/openpylon/**
- Tailwind CSS v4 via @tailwindcss/vite
- shadcn/ui initialized with 12 components
- All app dependencies: Zustand, zundo, dnd-kit, Framer Motion,
  Zod, ulid, date-fns, react-markdown, remark-gfm
- Path alias @/* configured in tsconfig + vite

components.json

@@ -0,0 +1,23 @@
+{
+  "$schema": "https://ui.shadcn.com/schema.json",
+  "style": "new-york",
+  "rsc": false,
+  "tsx": true,
+  "tailwind": {
+    "config": "",
+    "css": "src/index.css",
+    "baseColor": "neutral",
+    "cssVariables": true,
+    "prefix": ""
+  },
+  "iconLibrary": "lucide",
+  "rtl": false,
+  "aliases": {
+    "components": "@/components",
+    "utils": "@/lib/utils",
+    "ui": "@/components/ui",
+    "lib": "@/lib",
+    "hooks": "@/hooks"
+  },
+  "registries": {}
+}