SSR migrated to Rust

cores/mizan-rust-ssr/tests/fixture/runner.cjs

@@ -0,0 +1,29 @@
+// Proxy for the embedded-V8 runtime: a bare global context with no Node
+// builtins. Load the IIFE bundle (which assigns globalThis.renderApp) and call
+// it. What renders here renders in rusty_v8 — the engine swaps, the contract
+// (bundle defines a global render fn over a bare context) does not.
+const fs = require("fs")
+const vm = require("vm")
+
+const code = fs.readFileSync(__dirname + "/bundle.js", "utf8")
+
+// The minimal host globals React's bundle touches at init / sync render. The
+// rusty_v8 engine must provide the same set — this list is the spec for it.
+const sandbox = {
+  console, setTimeout, clearTimeout, queueMicrotask, MessageChannel, performance,
+  TextEncoder, TextDecoder,
+}
+sandbox.globalThis = sandbox
+
+vm.createContext(sandbox)
+vm.runInContext(code, sandbox)
+
+const html = sandbox.renderApp({ name: "World" })
+console.log("RENDERED:", html)
+
+const expected = '<div id="greeting">Hello, World!</div>'
+if (html !== expected) {
+  console.error("MISMATCH — expected:", expected)
+  process.exit(1)
+}
+console.log("OK — React bundle renders in a bare JS context (V8 proxy)")