Simplify the wide-layout details panel: floating-only on iPhone, side as a preset setting

iPhone landscape now uses the floating panel only, always on the right;
the pin and side-toggle buttons on the grabber are gone and the pinned
setting resolves to false on phone.

iPad and macOS default to the pinned side-by-side layout, keep the pin
button to switch to floating, and pick the panel side in the preset's
panel settings instead of an on-screen arrow. The pinned state persists
as a layout preference: closing the player or the hidden default
visibility no longer resets it.

Removes PanelAlignmentButton, the global floatingDetailsPanelSide setting
and its key, FloatingPanelSide.opposite, and the legacy
wideLayoutPanelAlignment preset field.

Yattee/Models/PlayerControls/PanelSettings.swift

@@ -359,16 +359,22 @@ struct PanelSettings: Codable, Hashable, Sendable {
     /// Whether the page bar shows labels next to icons.
     var showPageBarLabels: Bool?
 
+    /// Which side the details panel sits on in the standard wide layout on
+    /// iPad/macOS. iPhone ignores it (always right). Effective default: `.right`.
+    var wideLayoutSide: FloatingPanelSide?
+
     init(
         pages: [PanelPageConfiguration],
         layoutMode: PanelLayoutMode? = nil,
         defaultVisibility: PanelDefaultVisibility? = nil,
-        showPageBarLabels: Bool? = nil
+        showPageBarLabels: Bool? = nil,
+        wideLayoutSide: FloatingPanelSide? = nil
     ) {
         self.pages = pages
         self.layoutMode = layoutMode
         self.defaultVisibility = defaultVisibility
         self.showPageBarLabels = showPageBarLabels
+        self.wideLayoutSide = wideLayoutSide
     }
 
     /// In-memory cache of the active preset's panel settings, refreshed by the
@@ -388,6 +394,7 @@ struct PanelSettings: Codable, Hashable, Sendable {
     var effectiveLayoutMode: PanelLayoutMode { layoutMode ?? .stacked }
     var effectiveDefaultVisibility: PanelDefaultVisibility { defaultVisibility ?? .hidden }
     var effectiveShowPageBarLabels: Bool { showPageBarLabels ?? true }
+    var effectiveWideLayoutSide: FloatingPanelSide { wideLayoutSide ?? .right }
 
     /// Pages the panel should offer, in order. Pass a region to filter for
     /// corner mode; `nil` returns enabled pages from all regions.
@@ -488,6 +495,7 @@ struct PanelSettings: Codable, Hashable, Sendable {
         case layoutMode
         case defaultVisibility
         case showPageBarLabels
+        case wideLayoutSide
     }
 
     init(from decoder: Decoder) throws {
@@ -509,6 +517,7 @@ struct PanelSettings: Codable, Hashable, Sendable {
         layoutMode = try? container.decodeIfPresent(PanelLayoutMode.self, forKey: .layoutMode)
         defaultVisibility = try? container.decodeIfPresent(PanelDefaultVisibility.self, forKey: .defaultVisibility)
         showPageBarLabels = try container.decodeIfPresent(Bool.self, forKey: .showPageBarLabels)
+        wideLayoutSide = try? container.decodeIfPresent(FloatingPanelSide.self, forKey: .wideLayoutSide)
     }
 
     func encode(to encoder: Encoder) throws {
@@ -517,6 +526,7 @@ struct PanelSettings: Codable, Hashable, Sendable {
         try container.encodeIfPresent(layoutMode, forKey: .layoutMode)
         try container.encodeIfPresent(defaultVisibility, forKey: .defaultVisibility)
         try container.encodeIfPresent(showPageBarLabels, forKey: .showPageBarLabels)
+        try container.encodeIfPresent(wideLayoutSide, forKey: .wideLayoutSide)
     }
 }
 

Yattee/Models/PlayerControls/PlayerControlsLayout.swift

@@ -33,11 +33,6 @@ struct PlayerControlsLayout: Codable, Hashable, Sendable {
     /// Mini player settings. Optional for backward compatibility.
     var miniPlayerSettings: MiniPlayerSettings?
 
-    /// Unused: the player reads the panel side from SettingsManager
-    /// (`floatingDetailsPanelSide`). Kept only so old presets that saved this
-    /// field still decode.
-    var wideLayoutPanelAlignment: FloatingPanelSide?
-
     /// Details panel pages configuration. Optional for backward compatibility.
     var panelSettings: PanelSettings?