Fix broken scripts/test-capture-ipc.mjs harness

[false200]

What is this about?

Problem

The capture IPC test script is out of date and won't run as-is:

• References preload.js but the real file is preload.cjs
• Calls capturePrimaryScreen with old { onHide, onShow } API; real signature is (win, applyStealth) per ai/capture.js

Where to look

• scripts/test-capture-ipc.mjs
• ai/capture.js — current API
• preload.cjs — correct preload path

Acceptance criteria

• Script runs with documented command (e.g. npx electron scripts/test-capture-ipc.mjs)
• Uses correct preload path and capture API
• Prints clear OK/ERR result

Skills needed

Read existing code and align a script — good "code archaeology" starter task.