v0.7.4 — wp.org submission cleanup: remove updater + add LICENSE

Walks back v0.7.3's Update URI guard pattern. Plugin Check raised
`plugin_updater_detected` on the v0.7.3 build:

    "Including An Update Checker / Changing Updates functionality.
     Plugin Updater detected. Use of the Update URI header is not
     allowed in plugins hosted on WordPress.org."

PCP scans the source as-shipped, not as-distributed, so the v0.7.3
build-time `sed` strip never had a chance to run before the scan.
The simpler correct answer is to delete the custom updater entirely
and rely on wp.org as the canonical update channel once accepted.

Removed:
* `inc/updater.php` — recoverable from git history at tag v0.7.3 if
  ever needed for a non-wp.org distribution.
* `Update URI:` header line in `radio.php` (plus the NOTE block).
* `require_once RADIO_PATH . 'inc/updater.php';` in `radio.php`.
* Updates panel render + `function_exists()` guard in `inc/settings.php`.
* "Self-hosted update checker" line in `README.md`.
* "Self-hosted updater" bullet in `readme.txt` Privacy section.

Added (GPL declaration loop closed):
* `LICENSE` — verbatim canonical GPL v2 text (338 lines from
  gnu.org/licenses/gpl-2.0.txt).
* GPL header block in `assets/css/radio.css`.
* GPL header block in `assets/js/radio.js` (original module overview
  preserved verbatim below the license header).
* GPL header block in `radio.php` docblock alongside the existing
  `License:` / `License URI:` fields.

Migration: existing Gitea-installed copies of v0.7.3 or earlier
become orphaned of auto-updates after this lands on them (the
updater code is gone, so nothing advertises newer versions back).
Recommended path is to uninstall + reinstall from wp.org once the
plugin is accepted. No data loss — station + volume + theme +
history + favourites all live in user_meta.

No user-visible behaviour changes for the player itself. Only the
small `Updates` panel that sat at the bottom of Radio → Settings
is gone.

readme.txt

@@ -4,7 +4,7 @@ Donate link: https://buymeacoffee.com/davidtkeane
 Tags: radio, music, audio, internet radio, background music
 Requires at least: 5.3
 Tested up to: 7.0
-Stable tag: 0.7.3
+Stable tag: 0.7.4
 Requires PHP: 7.4
 License: GPLv2 or later
 License URI: https://www.gnu.org/licenses/gpl-2.0.html
@@ -42,7 +42,7 @@ RangerHQ Radio is privacy-respecting by design:
 * **Current-track display** polls SomaFM's public songs endpoint (`https://somafm.com/songs/{station}.json`) every 30 seconds **while audio is playing**. The plugin sends no identifying information with this request. Polling stops the moment you pause.
 * **Search-provider links** (Spotify / YouTube / Apple Music / Bandcamp) are outbound only. Clicking one opens a new tab with a search URL on that service — the plugin sends no data and stores no information about which links you click.
 * **No third-party JavaScript** is loaded from outside your own server. All scripts ship inside the plugin.
-* **Self-hosted updater** (`inc/updater.php`) is included in the WordPress.org distribution but is automatically disabled — WordPress.org handles updates per the directory guidelines. The code is only active when the plugin is installed from the author's own Gitea instance.
+* **Updates** come from WordPress.org through the normal WordPress core update process. The plugin does not contact any other update server.
 
 If you do not want any third-party traffic at all, simply do not press Play.
 
@@ -86,6 +86,9 @@ SomaFM's track-info endpoint (`somafm.com/songs/{station}.json`) is fetched best
 
 == Changelog ==
 
+= 0.7.4 =
+* WordPress.org submission cleanup. Removed the self-hosted Gitea updater (`inc/updater.php`) and the `Update URI` header from `radio.php`. WordPress.org explicitly disallows both for hosted plugins (Plugin Check `plugin_updater_detected`), so updates now flow through WordPress.org as the canonical channel. Added a top-level `LICENSE` file with the full GPL v2 text and explicit GPL header blocks to `assets/css/radio.css` and `assets/js/radio.js` so the licensing of every shipped file is unambiguous. The small `Updates` panel that used to sit at the bottom of Radio → Settings is gone; player behaviour is unchanged.
+
 = 0.7.3 =
 * WordPress.org guideline 8 compliance + Privacy documentation. Added `Update URI: https://git.davidtkeane.com/ranger/a-radio` header so installs from the author's Gitea continue to receive updates from there, while wp.org-distributed copies (where the build script strips this line) hand update delivery to WordPress.org — the self-hosted updater short-circuits at load time and the Updates panel hides automatically. Added a dedicated `== Privacy ==` section to the readme covering every outbound connection (none from the plugin itself; SomaFM audio + 30-second songs.json poll while playing). Added explicit link to SomaFM's terms of use at https://somafm.com/legal/. No user-visible behaviour changes.
 
@@ -127,6 +130,9 @@ SomaFM's track-info endpoint (`somafm.com/songs/{station}.json`) is fetched best
 
 == Upgrade Notice ==
 
+= 0.7.4 =
+WordPress.org submission cleanup — removes the disallowed self-hosted updater + `Update URI` header. Adds LICENSE file + per-asset GPL headers. The `Updates` panel in Settings is gone (WordPress.org handles updates now). No player behaviour changes.
+
 = 0.7.3 =
 WordPress.org submission compliance — adds `Update URI` header so the self-hosted updater stays dormant on wp.org installs (guideline 8). Adds Privacy section + SomaFM terms link. No user-visible changes.