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/ViewModels/PlayerControls/PlayerControlsSettingsViewModel.swift

@@ -818,6 +818,18 @@ final class PlayerControlsSettingsViewModel {
         }
     }
 
+    /// Current panel side in the standard wide layout (iPad/macOS).
+    var panelWideLayoutSide: FloatingPanelSide {
+        panelSettings.effectiveWideLayoutSide
+    }
+
+    /// Synchronously updates the panel side in the standard wide layout.
+    func syncPanelWideLayoutSide(_ side: FloatingPanelSide) {
+        updatePanelSettingsSync { settings in
+            settings.wideLayoutSide = side
+        }
+    }
+
     /// Synchronously updates a page's corner-layout region assignment.
     func setPanelPageRegion(_ region: PanelRegion, for pageType: PanelPageType) {
         updatePanelSettingsSync { settings in