feat(0.7.2): screenshots + correct wp.org contributor handle

Two small submission-prep moves on top of v0.7.1:

Added
- Five screenshots at the plugin root, per WordPress.org convention:
  screenshot-1.png  Dashboard widget
  screenshot-2.png  Settings page
  screenshot-3.png  History page (star + four search-provider links)
  screenshot-4.png  Pop-out mini-player window
  screenshot-5.png  About page
  Sizes 1087–1422 wide; total ~720KB.

Changed
- Contributors: in readme.txt updated from `davidtkeane` (placeholder)
  to `ir240474` (actual wp.org username, profile confirmed at
  https://profiles.wordpress.org/ir240474/).
- Stable tag: bumped to 0.7.2.
- Screenshots section in readme.txt rewritten to match the five
  actual screenshots.

Notes
- Source images were in an images/ working folder; moved + renamed to
  plugin root for wp.org convention, working folder removed.
- After this release the only PCP residue is the .gitignore
  hidden-file warning — unavoidable on the dev install, won't be in
  the submission zip.

Files: radio.php (version), readme.txt (Contributors / Stable Tag /
Screenshots section / new 0.7.2 changelog + upgrade notice),
CHANGELOG.md, inc/about.php (rotate v0.7.2 → latest),
5 new screenshot-*.png files at plugin root, images/ removed.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

radio.php

@@ -5,7 +5,7 @@
  * Plugin Name: RangerHQ Radio
  * Plugin URI:  https://icanhelp.ie/radio
  * Description: A small, focused internet radio player for your WordPress admin. 44 hand-curated stations from SomaFM across 10 genres — ambient, electronic, lounge, rock, metal, jazz, world, reggae, holiday, specials. Plays via HTML5 audio; per-user station + volume + history + favourites; pop-out window for continuous background play.
- * Version:     0.7.1
+ * Version:     0.7.2
  * Requires at least: 5.3
  * Requires PHP: 7.4
  * Author:      David Keane
@@ -20,7 +20,7 @@
 if ( ! defined( 'ABSPATH' ) ) { exit; }
 
 // Plugin coordinates.
-if ( ! defined( 'RADIO_VERSION' ) )     { define( 'RADIO_VERSION',     '0.7.1' ); }
+if ( ! defined( 'RADIO_VERSION' ) )     { define( 'RADIO_VERSION',     '0.7.2' ); }
 if ( ! defined( 'RADIO_FILE' ) )        { define( 'RADIO_FILE',        __FILE__ ); }
 if ( ! defined( 'RADIO_PATH' ) )        { define( 'RADIO_PATH',        plugin_dir_path( __FILE__ ) ); }
 if ( ! defined( 'RADIO_URL' ) )         { define( 'RADIO_URL',         plugin_dir_url( __FILE__ ) ); }