feat: power reference site with in-process WIP WASM

Add the public-document Worldspace, Rust Client/Host bridge, and WIP-backed tree and document rendering while preserving static fallback and navigation.

Pin the Rust source and build tools, verify resource and trap boundaries, and cover dev and preview loading including same-origin generated module URLs.

site/package.json

@@ -7,13 +7,19 @@
     "node": ">=22.12.0"
   },
   "scripts": {
+    "build:wasm": "node scripts/build-wasm.mjs",
+    "predev": "npm run build:wasm",
+    "prebuild": "npm run build:wasm",
+    "test:rust": "cargo test --workspace --locked",
     "dev": "astro dev",
     "check": "astro check",
     "test": "node --test tests/*.test.mjs",
     "build": "astro build",
     "check:links": "node scripts/check-links.mjs",
     "verify": "npm run test && npm run check && npm run build && npm run check:links",
+    "pretest:browser": "node scripts/build-wasm.mjs --test-probes",
     "test:browser": "playwright test",
+    "test:dev": "playwright test --config playwright.dev.config.ts",
     "preview": "astro preview"
   },
   "dependencies": {