feat: v0.2.0 — UI rebuilt to WordPress admin standards

v0.1.0 worked but felt like a third-party React widget bolted on
top of WordPress. v0.2.0 makes the player visually native to the
WP admin: postbox container, standard Play/Pause button with text
label, admin-colour-scheme aware accents, dashboard widget no
longer renders a card inside a card.

CHANGES
- inc/admin-page.php: main page now wraps the player in a
  .postbox > .postbox-header (with h2.hndle) > .inside structure.
  Custom rounded card / shadow stripped.
- inc/dashboard-widget.php: bare .radio-player content; WP already
  wraps dashboard widgets in a postbox, was double-card before.
- inc/about.php: version-history card promotes v0.2.0 to latest,
  demotes v0.1.0.
- assets/css/radio.css: rewrite. Strip custom shadows + oversized
  typography. Adopt WP body-text defaults. Use
  var(--wp-admin-theme-color, #2271b1) for volume-slider accent +
  link colours so the plugin picks up whichever admin colour
  scheme the user has chosen. About-page cards now use the
  postbox-style gray header + 1px border pattern.
- assets/js/radio.js: setPlayIcon() also flips the visible text
  label ("Play" ↔ "Pause"), not just the icon class. mirrorSelection()
  also updates the [data-radio-genre] element so the genre label
  stays in sync across surfaces.
- radio.php: Version: 0.1.0 -> 0.2.0; BUDDY_VERSION constant
  bumped likewise.
- CHANGELOG.md: new [0.2.0] entry explaining the visual overhaul.

NET EFFECT
- Same 44 stations, same audio path, same persistence, same
  updater, same AJAX endpoint. Pure visual change.
- The plugin now looks like part of WordPress admin instead of a
  guest widget.
- Closer to WP.org submission criteria — plugin reviewers look
  for native-styled plugins.

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

assets/js/radio.js

@@ -42,11 +42,16 @@
         }).catch(function () { /* swallow — local UI already updated */ });
     }
 
-    /** Update play/pause button icon to reflect current audio state. */
+    /** Update play/pause button icon + label to reflect current audio state. */
     function setPlayIcon(btn, playing) {
         var icon = btn.querySelector('.dashicons');
-        if (!icon) { return; }
-        icon.className = 'dashicons ' + (playing ? 'dashicons-controls-pause' : 'dashicons-controls-play');
+        var label = btn.querySelector('[data-radio-play-label]');
+        if (icon) {
+            icon.className = 'dashicons ' + (playing ? 'dashicons-controls-pause' : 'dashicons-controls-play');
+        }
+        if (label) {
+            label.textContent = playing ? (cfg.strings.pause || 'Pause') : (cfg.strings.play || 'Play');
+        }
         btn.setAttribute('title', playing ? (cfg.strings.pause || 'Pause') : (cfg.strings.play || 'Play'));
     }
 
@@ -122,6 +127,8 @@
             audio.load();
             if (nameEl) { nameEl.textContent = s.name; }
             if (descEl) { descEl.textContent = s.description || ''; }
+            var genreEl = player.querySelector('[data-radio-genre]');
+            if (genreEl) { genreEl.textContent = s.genre || ''; }
             // Mirror selection to any OTHER .radio-player surfaces on the page.
             mirrorSelection(player, newId);
             saveState({ station_id: newId });
@@ -157,8 +164,10 @@
                 if (s) {
                     var nm = other.querySelector('[data-radio-name]');
                     var dc = other.querySelector('[data-radio-desc]');
+                    var gn = other.querySelector('[data-radio-genre]');
                     if (nm) { nm.textContent = s.name; }
                     if (dc) { dc.textContent = s.description || ''; }
+                    if (gn) { gn.textContent = s.genre || ''; }
                 }
             }
         });