Fix broken module script and dangling asset links

[tomayac]

Three console errors that are visible on the deployed demos at https://chrome.dev/web-ai-demos/. Found while checking every demo's console after a deploy; each is independent, so they can be split if preferred.

right-click-for-superpowers — demo never ran

script.js is an ES module (it starts with import {FilesetResolver, LlmInference} from …) but index.html loaded it as a classic script:

<script type="text/javascript" src="script.js"></script>

Every visit failed with Uncaught SyntaxError: Cannot use import statement outside a module, so none of the demo's code executed. Now type="module".

With that fixed the script runs and reaches Failed to initialize the task, which is the demo's documented placeholder state — MODEL_FILE_NAME is still 'https://', and the readme asks you to host your own Gemma model from Kaggle and point the code at it. That part is unchanged and intentional.

firebase-ai-logic, summarization-api-playground, summary-of-summaries — 404 favicon

All three carried <link rel="icon" type="image/svg+xml" href="/vite.svg" /> from the create-vite scaffold. None of the three ships vite.svg, or any icon asset at all, so the only effect was a 404 in the console. Removed.

wordup — 404 web app manifest

wordup shipped two identical manifests:

• public/manifest.json, linked by hand from index.html
• manifest.webmanifest, generated and injected by vite-plugin-pwa

chrome.dev does not serve .webmanifest files, so the injected link 404'd while the hand-written one resolved. Rather than leave the duplication, manifestFilename now makes vite-plugin-pwa emit manifest.json, and the redundant static copy and its hand-written <link> are gone — the plugin owns the manifest, generated from the manifest block already in vite.config.ts.

Verified against a build:

$ ls dist | grep -i manifest
manifest.json

$ grep -oE '<link[^>]*manifest[^>]*>' dist/index.html
<link rel="manifest" href="/web-ai-demos/wordup/manifest.json">

and the service worker precaches manifest.json.