refactor(themes): make the Now Playing page fully themeable (#1038)

* refactor(themes): drive the Now Playing page from semantic tokens

Replace the hardcoded white/black colours in the Now Playing dashboard,
the info-card glass panels, the queue sidebar, track lists, tags and the
Last.fm stats with the semantic token surface (text / surface / border /
glass). Light themes now render the page legibly instead of washed-out
white-on-light; dark themes keep their look because the tokens' dark values
match the previous hardcoded ones. Cover-art content (fullscreen player,
hero) is intentionally left fixed and out of scope.

* docs: CHANGELOG for themeable Now Playing page (#1038)

CHANGELOG.md

@@ -56,7 +56,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Themes — community Theme Store
 
-**By [@Psychotoxical](https://github.com/Psychotoxical), PR [#1009](https://github.com/Psychotoxical/psysonic/pull/1009), [#1011](https://github.com/Psychotoxical/psysonic/pull/1011), [#1012](https://github.com/Psychotoxical/psysonic/pull/1012), [#1013](https://github.com/Psychotoxical/psysonic/pull/1013), [#1014](https://github.com/Psychotoxical/psysonic/pull/1014), [#1015](https://github.com/Psychotoxical/psysonic/pull/1015), [#1016](https://github.com/Psychotoxical/psysonic/pull/1016), [#1018](https://github.com/Psychotoxical/psysonic/pull/1018), [#1020](https://github.com/Psychotoxical/psysonic/pull/1020), [#1036](https://github.com/Psychotoxical/psysonic/pull/1036)**
+**By [@Psychotoxical](https://github.com/Psychotoxical), PR [#1009](https://github.com/Psychotoxical/psysonic/pull/1009), [#1011](https://github.com/Psychotoxical/psysonic/pull/1011), [#1012](https://github.com/Psychotoxical/psysonic/pull/1012), [#1013](https://github.com/Psychotoxical/psysonic/pull/1013), [#1014](https://github.com/Psychotoxical/psysonic/pull/1014), [#1015](https://github.com/Psychotoxical/psysonic/pull/1015), [#1016](https://github.com/Psychotoxical/psysonic/pull/1016), [#1018](https://github.com/Psychotoxical/psysonic/pull/1018), [#1020](https://github.com/Psychotoxical/psysonic/pull/1020), [#1036](https://github.com/Psychotoxical/psysonic/pull/1036), [#1038](https://github.com/Psychotoxical/psysonic/pull/1038)**
 
 * New **Settings → Themes** tab: pick a theme, set the day/night scheduler, and browse a built-in **Theme Store** to install, update and uninstall community themes — with search, a dark/light filter, and full-size thumbnail previews.
 * The app now bundles six core themes (Catppuccin Mocha & Latte, Kanagawa Wave, Stark HUD, and the colour-blind-safe Vision Dark / Vision Navy); every other palette installs on demand from the [psysonic-themes](https://github.com/Psysonic/psysonic-themes) repo. Installed themes are saved locally and apply instantly at startup, even offline.
@@ -64,6 +64,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * Themes are **free-form** — beyond recolouring, they can add their own styling and animations and react to playback / fullscreen / sidebar / lyrics state. A safety floor (no network, no scripts) is always enforced; store themes are reviewed, and imported themes install at your own risk.
 * The store paginates large catalogues, and refreshing the list no longer jumps back to the top.
 * Each store theme shows its **total downloads** and a **last-changed** date, and can be sorted by most popular, newest or name; the catalogue now has numbered page navigation. These stats refresh once a day.
+* The **Now Playing** page now follows the active theme end to end — light themes render it legibly instead of washed-out, with no per-theme tweaks needed.
 * Upgrading from an older build: an active or scheduled theme that has moved to the store and isn't installed falls back to Mocha (dark) / Latte (light).