refactor:

- dedupe flash / highlighting logic
- codemirror logic now lives only in codemirror package
- remove old highlighting logic
- use codemirror package in react package
- cleanup CodeMirror6.jsx
- pull setMiniLocations into useHighlighting
- migrate MiniRepl, nano-repl + Repl to new highlighting

packages/codemirror/vite.config.js

@@ -7,7 +7,7 @@ export default defineConfig({
   plugins: [],
   build: {
     lib: {
-      entry: resolve(__dirname, 'codemirror.mjs'),
+      entry: resolve(__dirname, 'index.mjs'),
       formats: ['es', 'cjs'],
       fileName: (ext) => ({ es: 'index.mjs', cjs: 'index.js' }[ext]),
     },