[kitlangton]

Labs cards show their own settings, and stable builds no longer list Voice Filter or Playground

Before: pressing a Labs card opened a drawer from the right, with a "A short preview goes here" placeholder and a second copy of the switch. Unload model when idle and Screenshots kept their settings in that drawer. Stable builds listed Voice Filter and Playground.

After: there is no drawer. Each card shows its description and switch, and a lab's own settings (Unload after; the Screenshots shortcut and Saves to) show on its card while it's on. hex://labs/<lab> opens Labs on that lab's group. Voice Filter and Playground are Dev labs. A stable build doesn't route audio into Hex Microphone. If the macOS driver is still installed, the Voice Filter pane stays and shows only Uninstall, then goes away once the driver is gone. The filter code is kept for Muffle (#1391).

  Feature::VoiceFilter.audience()  -> Everyone
+ Feature::VoiceFilter.audience()  -> Dev
  Feature::Playground.audience()   -> Everyone
+ Feature::Playground.audience()   -> Dev

  card.on_press  -> open drawer(lab)
+ card         -> description + switch + extras(lab) while on
- labs/drawer.rs, group::Place, 9 drawer strings
+ fun::uninstall_row   // stable build, driver installed

Before	After

Read: src/rune_ui/labs/store.rs (card), src/rune_ui/fun.rs (stable uninstall), src/rune_ui/platform.rs (driver status polling). Tests: a_stable_build_offers_only_uninstall_for_an_installed_driver, a_stable_build_has_no_playground_or_voice_filter_lab, unload_when_idle_shows_its_minutes_on_its_card_while_on.