feat(editor): mermaid code editor & improve parsing (#10897)

excalidraw-app/vite.config.mts

@@ -106,6 +106,10 @@ export default defineConfig(({ mode }) => {
             if (id.includes("@excalidraw/mermaid-to-excalidraw")) {
               return "mermaid-to-excalidraw";
             }
+
+            if (id.includes("@codemirror/") || id.includes("@lezer/")) {
+              return "codemirror.chunk";
+            }
           },
         },
       },
@@ -150,6 +154,11 @@ export default defineConfig(({ mode }) => {
             "**/locales/**",
             "service-worker.js",
             "**/*.chunk-*.js",
+            // CodeMirrorEditor can't be assigned a `.chunk` name via
+            // manualChunks because Rollup would hoist shared deps (React)
+            // via a static import from the main bundle, defeating lazy
+            // loading. So we exclude it by name instead.
+            "**/CodeMirrorEditor-*.js",
           ],
           runtimeCaching: [
             {
@@ -189,7 +198,7 @@ export default defineConfig(({ mode }) => {
               },
             },
             {
-              urlPattern: new RegExp(".chunk-.+.js"),
+              urlPattern: new RegExp("(.chunk-.+|CodeMirrorEditor-.+)\\.js"),
               handler: "CacheFirst",
               options: {
                 cacheName: "chunk",