Move contents of heynote-electron subdirectory into git repo root

public/langdetect-worker.js

@@ -0,0 +1,19 @@
+importScripts("highlight.min.js")
+
+const HIGHLIGHTJS_LANGUAGES = ["json", "python", "javascript", "html", "sql", "java", "plaintext"]
+
+onmessage = (event) => {
+    //console.log("worker received message:", event.data)
+    //importScripts("../../lib/highlight.min.js")
+
+    const result = self.hljs.highlightAuto(event.data.content, HIGHLIGHTJS_LANGUAGES);
+    postMessage({
+        highlightjs: {
+            language: result.language,
+            relevance: result.relevance,
+            illegal: result.illegal,
+        },
+        content: event.data.content,
+        idx: event.data.idx,
+    })
+}