Prepare WP Puller metadata, licensing, and readme for WordPress.org directory submission

[Copilot]

This PR addresses WordPress.org listing blockers by adding a compliant plugin-directory readme.txt, replacing placeholder plugin header metadata, and aligning license declarations across the project. It also documents required third-party service calls used by the plugin.

• WordPress.org readme compliance

  • Added readme.txt in WordPress.org format with required headers:
    • Contributors, Tags, Requires at least, Tested up to, Requires PHP, Stable tag, License, License URI
  • Added required sections:
    • == Description ==, == Installation ==, == Frequently Asked Questions ==, == Screenshots ==, == Changelog ==
  • Set Stable tag: 1.0.8 to match the plugin version.

• Plugin header cleanup

  • Replaced placeholder author metadata in wp-puller/wp-puller.php.
  • Updated header licensing to:
    • License: GPLv2 or later
    • License URI: https://www.gnu.org/licenses/gpl-2.0.html

• License reconciliation

  • Updated both LICENSE files (repo root and plugin dir) to GPLv2-or-later text.
  • Updated README.md license references/badge to match GPLv2-or-later.

• External service disclosure (directory guideline requirement)

  • Documented outbound calls in readme.txt:
    • https://api.github.com for repository metadata and zipball download
    • https://www.cloudflare.com/ips-v4 and https://www.cloudflare.com/ips-v6 for trusted-proxy range refresh (with bundled fallback ranges)

Example metadata update in plugin header:

 * Author: Codician Team
 * Author URI: https://github.com/codician-team
 * License: GPLv2 or later
 * License URI: https://www.gnu.org/licenses/gpl-2.0.html

[altugank]

make contributor codician team