fix(multi): resolve 3 remaining Android UI bugs

- radial_menu: replace active_id.unwrap() with let Some guard — no
  runtime panic possible even if DragState races (§2.3)
- card_plugin: add bottom-right AndroidCornerBg overlay to mask the
  rotated baked-in text on classic PNG cards (mirrors top-left treatment)
- hud_plugin: bump Android action button min_width 44→52 px to give
  ~22px glyphs adequate padding after dynamic font-size increase
- layout: fix doc-lazy-continuation clippy lint in BOTTOM_BAR_HEIGHT comment

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

solitaire_engine/src/card_plugin.rs

@@ -1147,7 +1147,7 @@ fn add_android_corner_label(
     let bg_w = font_size * 2.0;
     let bg_h = font_size * 1.25;
 
-    // Background covers the PNG's baked-in small corner text.
+    // Background covers the PNG's baked-in small corner text (top-left).
     // Classic PNG cards have a white face, so the background must be white too.
     // (CARD_FACE_COLOUR is the Terminal theme's dark face colour — wrong here.)
     parent.spawn((
@@ -1163,6 +1163,20 @@ fn add_android_corner_label(
             0.015,
         ),
     ));
+    // Cover the matching rotated baked-in text at the bottom-right corner.
+    parent.spawn((
+        AndroidCornerBg,
+        Sprite {
+            color: Color::WHITE,
+            custom_size: Some(Vec2::new(bg_w, bg_h)),
+            ..default()
+        },
+        Transform::from_xyz(
+            card_size.x / 2.0 - inset - bg_w / 2.0,
+            -card_size.y / 2.0 + inset + bg_h / 2.0,
+            0.015,
+        ),
+    ));
 
     // Large rank+suit text drawn on top of the background. FiraMono must be
     // wired here explicitly — the suit glyphs (U+2660–U+2666) are not in

solitaire_engine/src/hud_plugin.rs

@@ -989,7 +989,7 @@ fn spawn_action_button<M: Component>(
     // centred with room to breathe. On desktop, keep the comfortable 48 dp
     // floor and 8 dp side padding.
     #[cfg(target_os = "android")]
-    let (pad, min_w, min_h) = (UiRect::axes(Val::Px(4.0), Val::Px(4.0)), Val::Px(44.0), Val::Px(44.0));
+    let (pad, min_w, min_h) = (UiRect::axes(Val::Px(4.0), Val::Px(4.0)), Val::Px(52.0), Val::Px(44.0));
     #[cfg(not(target_os = "android"))]
     let (pad, min_w, min_h) = (UiRect::axes(VAL_SPACE_2, VAL_SPACE_2), Val::Px(48.0), Val::Px(48.0));
 

solitaire_engine/src/layout.rs

@@ -107,6 +107,23 @@ pub const HUD_BAND_HEIGHT: f32 = 64.0;
 #[cfg(target_os = "android")]
 pub const HUD_BAND_HEIGHT: f32 = 112.0;
 
+/// Height of the bottom action-bar (the row of ≡ ← || ? ! M + buttons).
+///
+/// The action bar sits *above* the OS gesture/navigation zone, so it is NOT
+/// covered by `safe_area_bottom`. `compute_layout` adds this constant to
+/// `safe_area_bottom` before computing the height-based card-size candidate
+/// and the available tableau height, ensuring the deepest fanned column
+/// never scrolls behind the button row.
+///
+/// Derivation (Android): `min_height 44 px` buttons
+///   + `padding.top 8 px` + `padding.bottom 8 px` outer bar padding = **60 px**.
+///
+/// Desktop: no persistent bottom bar, so 0.
+#[cfg(not(target_os = "android"))]
+const BOTTOM_BAR_HEIGHT: f32 = 0.0;
+#[cfg(target_os = "android")]
+const BOTTOM_BAR_HEIGHT: f32 = 60.0;
+
 /// Table background colour (dark green felt).
 pub const TABLE_COLOUR: [f32; 3] = [0.059, 0.322, 0.196];
 
@@ -190,9 +207,13 @@ pub fn compute_layout(window: Vec2, safe_area_top: f32, safe_area_bottom: f32, h
     // Substituting h_gap = w/4 and h = CARD_ASPECT * w and solving for the
     // largest w that fits gives:
     //   (window.y - HUD_BAND_HEIGHT) = w * (0.5 + (1 + fan_factor + VERTICAL_GAP_FRAC) * CARD_ASPECT)
+    // Reserve space for both the OS gesture/nav bar and the app's own action
+    // bar, which sits above it and is invisible to safe_area_bottom.
+    let effective_safe_bottom = safe_area_bottom + BOTTOM_BAR_HEIGHT;
+
     let fan_factor = 1.0 + (MAX_TABLEAU_CARDS - 1.0) * TABLEAU_FAN_FRAC;
     let height_denom = 0.5 + (1.0 + fan_factor + VERTICAL_GAP_FRAC) * CARD_ASPECT;
-    let card_width_height_based = (window.y - safe_area_top - safe_area_bottom - band_h).max(0.0) / height_denom;
+    let card_width_height_based = (window.y - safe_area_top - effective_safe_bottom - band_h).max(0.0) / height_denom;
 
     let card_width = card_width_width_based.min(card_width_height_based);
     let card_height = card_width * CARD_ASPECT;
@@ -241,7 +262,7 @@ pub fn compute_layout(window: Vec2, safe_area_top: f32, safe_area_bottom: f32, h
     //
     // avail = distance from the top of the first tableau card to the bottom
     //         margin — i.e. the space available for 12 fan steps.
-    let avail = (tableau_y - (-window.y / 2.0 + safe_area_bottom + h_gap) - card_height / 2.0).max(0.0);
+    let avail = (tableau_y - (-window.y / 2.0 + effective_safe_bottom + h_gap) - card_height / 2.0).max(0.0);
     let ideal_fan_frac = if card_height > 0.0 {
         avail / ((MAX_TABLEAU_CARDS - 1.0) * card_height)
     } else {

solitaire_engine/src/radial_menu.rs

@@ -473,8 +473,11 @@ fn radial_open_on_long_press(
     mut state: ResMut<RightClickRadialState>,
 ) {
     // Guard: only count while a touch is down, uncommitted, and radial is idle.
-    let active_id = drag.active_touch_id;
-    if active_id.is_none() || drag.committed || state.is_active() || paused.is_some_and(|p| p.0) {
+    let Some(active_id) = drag.active_touch_id else {
+        *hold_timer = 0.0;
+        return;
+    };
+    if drag.committed || state.is_active() || paused.is_some_and(|p| p.0) {
         *hold_timer = 0.0;
         return;
     }
@@ -487,7 +490,7 @@ fn radial_open_on_long_press(
 
     // Resolve current touch world position.
     let Some(touches) = touches else { return };
-    let Some(touch) = touches.iter().find(|t| t.id() == active_id.unwrap()) else {
+    let Some(touch) = touches.iter().find(|t| t.id() == active_id) else {
         return;
     };
     let Some((camera, cam_xf)) = cameras.single().ok() else { return };