Update custom Electron to v39.2.13-qp20 for Windows

Fixes transparent frameless window resize issue. This version includes
the combined Chromium patch (WS_THICKFRAME) and Electron fix
(SetIsTranslucent post-task) for transparent+frameless+resizable windows.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: steveseguin

package.json

@@ -33,10 +33,10 @@
   "build": {
     "appId": "capture.electron",
     "productName": "elecap",
-    "electronVersion": "39.2.8-qp20",
+    "electronVersion": "39.2.13-qp20",
     "electronDownload": {
       "mirror": "https://github.com/steveseguin/electron/releases/download/",
-      "customDir": "v39.2.8-qp20"
+      "customDir": "v39.2.13-qp20"
     },
     "protocols": {
       "name": "electroncapture",

scripts/install-custom-electron.js

@@ -10,11 +10,11 @@ const { Readable } = require('stream');
 const CHECKSUM_MANIFEST = 'SHASUMS256.txt';
 const PLATFORM_TARGETS = new Map([
   ['win32', {
-    version: '39.2.7-qp20',
-    releaseTag: 'v39.2.7-qp20',
+    version: '39.2.13-qp20',
+    releaseTag: 'v39.2.13-qp20',
     mirrorBase: 'https://github.com/steveseguin/electron/releases/download/',
     artifacts: new Map([
-      ['x64', 'electron-v39.2.7-win32-x64.zip']
+      ['x64', 'electron-v39.2.13-qp20-win32-x64.zip']
     ])
   }],
   ['linux', {