fix(dev-server): invalidate WRN cache by content

packages/dev-server/test/pipeline.test.ts

@@ -1,5 +1,5 @@
 import { expect, test } from "bun:test";
-import { mkdtempSync, rmSync, writeFileSync } from "node:fs";
+import { mkdtempSync, rmSync, utimesSync, writeFileSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { invalidateModule, loadModule, setCompileCacheDir } from "../src/pipeline.ts";
@@ -41,3 +41,24 @@ test("invalidateModule recompiles changed WRN files in-process", async () => {
     rmSync(root, { recursive: true, force: true });
   }
 });
+
+test("WRN cache follows content when a replacement has an older mtime", async () => {
+  const root = mkdtempSync(join(tmpdir(), "wrnexus-cache-"));
+  const file = join(root, "component.wrn");
+  setCompileCacheDir(join(root, ".wrnexus"));
+
+  try {
+    writeFileSync(file, "component Example { view { <p>Old</p> } }\n");
+    const first = (await loadModule(file)).render as () => unknown;
+    expect(String(first())).toContain("Old");
+
+    writeFileSync(file, "component Example { view { <p>Current</p> } }\n");
+    utimesSync(file, new Date(0), new Date(0));
+    invalidateModule(file);
+
+    const current = (await loadModule(file)).render as () => unknown;
+    expect(String(current())).toContain("Current");
+  } finally {
+    rmSync(root, { recursive: true, force: true });
+  }
+});