Frontend uudelleenrakennettu: Astro-komponentit, Wasm pääsäikeessä, ei Workeria

Vanha frontend siirretty temp/. Uusi rakenne:
- StatusBar.astro, Terminal.astro, Editor.astro, Guide.astro
- global.css erillinen
- Wasm pääsäikeessä (ei Worker — yksinkertainen, debugattava)
- Tab-completion, dropdown, projektikortti, Monaco, GUIDE.md
- Ei tokenisointia eikä koodilaboratoriota

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

network-poc/frontend/node_modules/diff/CONTRIBUTING.md

@@ -0,0 +1,28 @@
+## Building and testing
+
+```
+yarn
+yarn test
+```
+
+To run tests in a *browser* (for instance to test compatibility with Firefox, with Safari, or with old browser versions), run `yarn karma start`, then open http://localhost:9876/ in the browser you want to test in. Results of the test run will appear in the terminal where `yarn karma start` is running.
+
+If you notice any problems, please report them to the GitHub issue tracker at
+[http://github.com/kpdecker/jsdiff/issues](http://github.com/kpdecker/jsdiff/issues).
+
+## Releasing
+
+Run a test in Firefox via the procedure above before releasing.
+
+A full release may be completed by first updating the `"version"` property in package.json, then running the following:
+
+```
+yarn clean
+yarn build
+yarn npm publish
+```
+
+After releasing, remember to:
+* commit the `package.json` change and push it to GitHub
+* create a new version tag on GitHub
+* update `diff.js` on the `gh-pages` branch to the latest built version from the `dist/` folder.