Scaffold Svelte frontend and browser test matrix

Establish the TypeScript 7, Oxlint, Vitest, and Playwright workspace with an isolated Svelte diagnostics compatibility boundary.

web/tsconfig.node.json

@@ -0,0 +1,12 @@
+{
+  "compilerOptions": {
+    "composite": true,
+    "module": "ESNext",
+    "moduleResolution": "Bundler",
+    "skipLibCheck": true,
+    "strict": true,
+    "target": "ES2024",
+    "tsBuildInfoFile": "./.cache/tsconfig.node.tsbuildinfo"
+  },
+  "include": ["*.config.ts"]
+}