chore: add frontend dependencies and update test fixtures

- Add react-router-dom, @tanstack/react-query, zustand, @headlessui/react
- Update pnpm workspace configuration
- Update test fixtures to reference OpenCode instead of RunFusion
- Add frontend environment variable examples
- Update .gitignore for .opencode and .sisyphus directories

apps/web/package.json

@@ -4,7 +4,9 @@
   "private": true,
   "type": "module",
   "pnpm": {
-    "onlyBuiltDependencies": ["esbuild"]
+    "onlyBuiltDependencies": [
+      "esbuild"
+    ]
   },
   "scripts": {
     "dev": "vite",
@@ -14,22 +16,32 @@
     "typecheck": "tsc -b --noEmit"
   },
   "dependencies": {
+    "@headlessui/react": "^2.2.10",
+    "@heroicons/react": "^2.2.0",
+    "@tanstack/react-query": "^5.100.10",
+    "clsx": "^2.1.1",
     "react": "^19.0.0",
-    "react-dom": "^19.0.0"
+    "react-dom": "^19.0.0",
+    "react-router-dom": "^7.15.0",
+    "tailwind-merge": "^3.6.0",
+    "zustand": "^5.0.13"
   },
   "devDependencies": {
+    "@eslint/js": "^9.24.0",
     "@testing-library/jest-dom": "^6.6.3",
     "@testing-library/react": "^16.3.0",
+    "@types/node": "^22.0.0",
     "@types/react": "^19.0.0",
     "@types/react-dom": "^19.0.0",
     "@vitejs/plugin-react": "^4.4.0",
-    "@eslint/js": "^9.24.0",
+    "autoprefixer": "^10.5.0",
     "eslint": "^9.24.0",
     "eslint-plugin-react-hooks": "^5.2.0",
     "eslint-plugin-react-refresh": "^0.4.19",
     "globals": "^16.0.0",
     "jsdom": "^26.0.0",
-    "@types/node": "^22.0.0",
+    "postcss": "^8.5.14",
+    "tailwindcss": "^4.3.0",
     "typescript": "~5.7.0",
     "typescript-eslint": "^8.29.0",
     "vite": "^6.3.0",