feat: initial scaffold of uniweb — unibus web frontend (SPA + gateway)

Extracted from unibus v0.13.0: the chat SPA (web/, React+Mantine, per-user
BIP39 wallet) and the web gateway (cmd/webgw, REST+SSE) that acts as a bus
peer for the browser. Consumes unibus as a Go module via replace => ../unibus,
keeping its own replace fn-registry for the cybersecurity primitives.

go build/vet/test and pnpm build green in the new location.

web/tsconfig.app.json

@@ -0,0 +1,21 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "useDefineForClassFields": true,
+    "lib": ["ES2022", "DOM", "DOM.Iterable"],
+    "module": "ESNext",
+    "skipLibCheck": true,
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "resolveJsonModule": true,
+    "isolatedModules": true,
+    "moduleDetection": "force",
+    "noEmit": true,
+    "jsx": "react-jsx",
+    "strict": true,
+    "noUnusedLocals": false,
+    "noUnusedParameters": false,
+    "noFallthroughCasesInSwitch": true
+  },
+  "include": ["src"]
+}