Fix SwiftLint and SwiftFormat violations

- Run SwiftFormat to fix indentation, spacing, and formatting issues
- Replace CGFloat with Double and NSRect with CGRect per style guide
- Remove redundant .center alignment specifications
- Remove unnecessary @available checks for satisfied deployment targets
- Fix closure brace indentation for consistency
- Disable closure_end_indentation rule to resolve SwiftFormat conflict

All linting checks now pass with zero errors and warnings.

macOS/InstancesSettings.swift

@@ -71,11 +71,7 @@ struct InstancesSettings: View {
                     }
                 }
 
-                if #available(macOS 12.0, *) {
-                    list.listStyle(.inset(alternatesRowBackgrounds: true))
-                } else {
-                    list.listStyle(.inset)
-                }
+                list.listStyle(.inset(alternatesRowBackgrounds: true))
             }
 
             if selectedInstance != nil, selectedInstance.app.hasFrontendURL {

macOS/VideoLayer.swift

@@ -37,7 +37,7 @@ final class VideoLayer: CAOpenGLLayer {
         displayTime _: UnsafePointer<CVTimeStamp>?
     ) {
         needsRedraw = false
-        
+
         var i: GLint = 0
         var flip: CInt = 1
         var ditherDepth = 8
@@ -103,7 +103,7 @@ final class VideoLayer: CAOpenGLLayer {
         needsRedraw = true
         super.display()
     }
-    
+
     func requestRedraw() {
         // Called from MPV's glUpdate callback - use setNeedsDisplay for efficient batching
         DispatchQueue.main.async { [weak self] in