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/hast-util-to-html/lib/handle/index.js

@@ -0,0 +1,47 @@
+/**
+ * @import {Nodes, Parents} from 'hast'
+ * @import {State} from '../index.js'
+ */
+
+import {zwitch} from 'zwitch'
+import {comment} from './comment.js'
+import {doctype} from './doctype.js'
+import {element} from './element.js'
+import {raw} from './raw.js'
+import {root} from './root.js'
+import {text} from './text.js'
+
+/**
+ * @type {(node: Nodes, index: number | undefined, parent: Parents | undefined, state: State) => string}
+ */
+export const handle = zwitch('type', {
+  invalid,
+  unknown,
+  handlers: {comment, doctype, element, raw, root, text}
+})
+
+/**
+ * Fail when a non-node is found in the tree.
+ *
+ * @param {unknown} node
+ *   Unknown value.
+ * @returns {never}
+ *   Never.
+ */
+function invalid(node) {
+  throw new Error('Expected node, not `' + node + '`')
+}
+
+/**
+ * Fail when a node with an unknown type is found in the tree.
+ *
+ * @param {unknown} node_
+ *  Unknown node.
+ * @returns {never}
+ *   Never.
+ */
+function unknown(node_) {
+  // `type` is guaranteed by runtime JS.
+  const node = /** @type {Nodes} */ (node_)
+  throw new Error('Cannot compile unknown node `' + node.type + '`')
+}