fix(cli): page closures survive keepNames transpilation; format motion-blur

Running the CLI from source (tsx dev script, as CI's smoke job does)
transpiles with keepNames, which rewrites named inner functions in
serialized page closures into __name(...) calls — a helper that exists
in the Node bundle but not in the browser realm. The unified seek
closure was the first validate-path page function with named inner
functions, so 'hyperframes validate' threw '__name is not defined' in
CI while the dist build worked. Every session opener now installs a
no-op __name shim via evaluateOnNewDocument before any page script
runs, immunizing all serialized closures regardless of build mode.

packages/cli/src/commands/validate.ts

@@ -15,6 +15,7 @@ import { resolveCompositionViewportFromHtml } from "../utils/compositionViewport
 import { c } from "../ui/colors.js";
 import { printDeprecationNotice, withMeta } from "../utils/updateCheck.js";
 import {
+  installPageFunctionGuard,
   resolveCliChromeGpuMode,
   seekCompositionTimeline,
 } from "../capture/captureCompositionFrame.js";
@@ -421,6 +422,7 @@ async function validateInBrowser(
     });
 
     const page = await chromeBrowser.newPage();
+    await installPageFunctionGuard(page);
     await page.setViewport(viewport);
 
     page.on("console", (msg) => {