Add Brave CDP automation, replace Oracle browser mode

Connects to user's running Brave via Chrome DevTools Protocol
to automate ChatGPT interaction. Uses puppeteer-core to open a
tab, send the prompt, wait for response, and extract the result.

No cookies, no separate profiles, no copy/paste. Just connects
to the browser where the user is already logged in.

One-time setup: relaunch Brave with --remote-debugging-port=9222

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

node_modules/tar-stream/constants.js

@@ -0,0 +1,14 @@
+const constants = { // just for envs without fs
+  S_IFMT: 61440,
+  S_IFDIR: 16384,
+  S_IFCHR: 8192,
+  S_IFBLK: 24576,
+  S_IFIFO: 4096,
+  S_IFLNK: 40960
+}
+
+try {
+  module.exports = require('fs').constants || constants
+} catch {
+  module.exports = constants
+}