feat: add Windows .exe support

- Add @electron-forge/maker-squirrel for Windows installer
- Create .ico icon from existing PNG
- Fix compositor platform detection for win32
- Forge config now builds both .dmg (macOS) and .exe (Windows)

forge.config.ts

@@ -2,16 +2,17 @@
  * Electron Forge Configuration — Bradly Desktop App
  *
  * Handles packaging and creating distributable installers.
- * Currently targets macOS (.dmg) only.
+ * Targets: macOS (.dmg) and Windows (.exe)
  */
 import type { ForgeConfig } from '@electron-forge/shared-types';
 import { MakerDMG } from '@electron-forge/maker-dmg';
+import { MakerSquirrel } from '@electron-forge/maker-squirrel';
 
 const config: ForgeConfig = {
   packagerConfig: {
     name: 'Bradly',
     executableName: 'bradly',
-    icon: './assets/icon',
+    icon: './assets/icon', // .icns for macOS, .ico for Windows (auto-resolved)
     asar: {
       // Remotion compositor binaries MUST be outside app.asar
       // because they are native executables that need direct filesystem access
@@ -43,9 +44,16 @@ const config: ForgeConfig = {
     ],
   },
   makers: [
+    // macOS installer
     new MakerDMG({
       format: 'ULFO',
     }),
+    // Windows installer (.exe)
+    new MakerSquirrel({
+      name: 'Bradly',
+      setupIcon: './assets/icon.ico',
+      iconUrl: 'https://raw.githubusercontent.com/kevdevg/Bradly/main/assets/icon.ico',
+    }),
   ],
 };