feat: add extension_paths parameter for loading Chrome extensions (#210)

Add `extension_paths` parameter to all launch functions (Python + JS) for loading Chrome extensions.

Resolves paths to absolute, injects `--load-extension` and `--disable-extensions-except` flags via `build_args()`.

Note: Extensions require a persistent context (`launch_persistent_context`) to function — this is a Chromium limitation.

Co-authored-by: zackycodes <75211659+zackycodes@users.noreply.github.com>

js/src/types.ts

@@ -17,6 +17,8 @@ export interface LaunchOptions {
   proxy?: string | { server: string; bypass?: string; username?: string; password?: string };
   /** Additional Chromium CLI arguments. */
   args?: string[];
+  /** Chrome extension paths to load. */
+  extensionPaths?: string[];
   /** Include default stealth fingerprint args (default: true). Set false to use custom --fingerprint flags. */
   stealthArgs?: boolean;
   /** IANA timezone, e.g. "America/New_York". Sets --fingerprint-timezone binary flag. */