feat(build): add esbuild bundler for Electron main process

build-main.config.js

@@ -0,0 +1,41 @@
+const esbuild = require('esbuild');
+const path = require('path');
+
+async function build() {
+  try {
+    console.log('Building main process with esbuild...');
+    
+    // Build main process
+    await esbuild.build({
+      entryPoints: ['src/apps/companion/main/index.ts'],
+      bundle: true,
+      platform: 'node',
+      target: 'node20',
+      format: 'cjs',
+      outfile: 'dist/main/apps/companion/main/index.js',
+      external: ['electron'],
+      sourcemap: true,
+      logLevel: 'info',
+    });
+    
+    // Build preload script
+    await esbuild.build({
+      entryPoints: ['src/apps/companion/main/preload.ts'],
+      bundle: true,
+      platform: 'node',
+      target: 'node20',
+      format: 'cjs',
+      outfile: 'dist/main/apps/companion/main/preload.js',
+      external: ['electron'],
+      sourcemap: true,
+      logLevel: 'info',
+    });
+    
+    console.log('✓ Main process and preload script built successfully');
+  } catch (error) {
+    console.error('✗ Build failed:', error);
+    process.exit(1);
+  }
+}
+
+build();