Just use file ext to identify indexable files to fix Desktop app install

- Magika on Desktop app was too bloated (100Mb to 250Mb) and broke
  install for some reason. Not sure why it was causing the app install
  to fail but do not have time to currently investigate

- Just use file extensions whitelist it's good enough for now. Let
  server handle the deeper identification of file type

src/interface/desktop/main.js

@@ -1,5 +1,4 @@
 const { app, BrowserWindow, ipcMain, Tray, Menu, nativeImage, shell } = require('electron');
-const Magika = require('magika').MagikaNode;
 const todesktop = require("@todesktop/runtime");
 const khojPackage = require('./package.json');
 
@@ -15,9 +14,13 @@ const KHOJ_URL = 'https://app.khoj.dev';
 
 const Store = require('electron-store');
 
-const magika = new Magika();
-let validFileTypes;
-const binaryFileTypes = ['pdf', 'png', 'jpg', 'jpeg']
+const textFileTypes = [
+    // Default valid file extensions supported by Khoj
+    'org', 'md', 'markdown', 'txt', 'html', 'xml',
+    // Other valid text file extensions from https://google.github.io/magika/model/config.json
+    'appleplist', 'asm', 'asp', 'batch', 'c', 'cs', 'css', 'csv', 'eml', 'go', 'html', 'ini', 'internetshortcut', 'java', 'javascript', 'json', 'latex', 'lisp', 'makefile', 'markdown', 'mht', 'mum', 'pem', 'perl', 'php', 'powershell', 'python', 'rdf', 'rst', 'rtf', 'ruby', 'rust', 'scala', 'shell', 'smali', 'sql', 'svg', 'symlinktext', 'txt', 'vba', 'winregistry', 'xml', 'yaml']
+const binaryFileTypes = ['pdf']
+const validFileTypes = textFileTypes.concat(binaryFileTypes);
 
 const schema = {
     files: {
@@ -68,7 +71,6 @@ const schema = {
     }
 };
 
-let isMagikaLoaded = false;
 let syncing = false;
 let state = {}
 const store = new Store({ schema });
@@ -113,24 +115,9 @@ function filenameToMimeType (filename) {
     }
 }
 
-async function isPlainTextFile(filePath) {
-    if (!isMagikaLoaded) {
-        await magika.load();
-        isMagikaLoaded = true;
-        validFileTypes = [
-            "org", "md", "pdf",
-            // all text file extensions known to Magika
-            ...magika.config.labels.filter(l => l.is_text == true).map(l => l.name)];
-    }
-    try {
-        const fileContent = fs.readFileSync(filePath);
-        const fileType = await magika.identifyBytes(fileContent);
-        const fileLabel = magika.config.labels.filter(l => l.name == fileType.label)?.[0]
-        return fileLabel?.is_text && validFileTypes.includes(fileType?.label);
-    } catch (err) {
-        console.error("Failed to identify file type: ", err);
-        return false;
-    }
+function isSupportedFileType(filePath) {
+    const fileExtension = filePath.split('.').pop();
+    return validFileTypes.includes(fileExtension);
 }
 
 async function processDirectory(filesToPush, folder) {
@@ -138,11 +125,16 @@ async function processDirectory(filesToPush, folder) {
 
     for (const file of files) {
         const filePath = path.join(file.path, file.name || '');
-        if (file.isFile() && await isPlainTextFile(filePath)) {
+        // Skip hidden files and folders
+        if (file.name.startsWith('.')) {
+            continue;
+        }
+        // Add supported files to index
+        if (file.isFile() && isSupportedFileType(filePath)) {
             console.log(`Add ${file.name} in ${file.path} for indexing`);
             filesToPush.push(filePath);
         }
-
+        // Recursively process subdirectories
         if (file.isDirectory()) {
             await processDirectory(filesToPush, {'path': filePath});
         }
@@ -262,15 +254,6 @@ async function pushDataToKhoj (regenerate = false) {
 pushDataToKhoj();
 
 async function handleFileOpen (type) {
-    if (!isMagikaLoaded) {
-        await magika.load();
-        isMagikaLoaded = true;
-        validFileTypes = [
-            "org", "md", "pdf",
-            // all text file extensions known to Magika
-            ...magika.config.labels.filter(l => l.is_text == true).map(l => l.name)];
-    }
-
     let { canceled, filePaths } = {canceled: true, filePaths: []};
     if (type === 'file') {
         ({ canceled, filePaths } = await dialog.showOpenDialog({properties: ['openFile' ], filters: [{ name: "Valid Khoj Files", extensions: validFileTypes }] }));