Fix compilation error of Swift Concurrency

Author: vnixx

Sources/REText/AsyncLayer.swift

@@ -342,7 +342,11 @@ public class AsyncLayer: CALayer, @unchecked Sendable {
              let isCancelled: @Sendable () -> Bool = { value != sentinel.value }
              let backgroundColor = (opaque && self.backgroundColor != nil) ? self.backgroundColor : nil
 
-             Task(priority: .high) {
+             // Capture self as nonisolated(unsafe) to avoid data race warnings
+             // This is safe because we only access self on the MainActor
+             nonisolated(unsafe) let unsafeSelf = self
+             
+             Task(priority: .high) { @Sendable in
                  await RenderActorPool.next().render {
                      if isCancelled() {
                          _ = backgroundColor
@@ -374,16 +378,16 @@ public class AsyncLayer: CALayer, @unchecked Sendable {
 
                      if isCancelled() {
                          await MainActor.run {
-                             task.didDisplay?(self, false)
+                             task.didDisplay?(unsafeSelf, false)
                          }
                          return
                      }
                      await MainActor.run {
                          if isCancelled() {
-                             task.didDisplay?(self, false)
+                             task.didDisplay?(unsafeSelf, false)
                          } else {
-                             self.contents = image.cgImage
-                             task.didDisplay?(self, true)
+                             unsafeSelf.contents = image.cgImage
+                             task.didDisplay?(unsafeSelf, true)
                          }
                      }
                  }

Sources/REText/Attributes/TextAttachment.swift

@@ -84,7 +84,10 @@ open class TextAttachment: NSTextAttachment, @unchecked Sendable {
     open var content: Content? {
         didSet {
             guard content != oldValue else { return }
-            syncOnMain { contentSize = content?.size ?? .zero }
+            nonisolated(unsafe) let unsafeSelf = self
+            MainActor.assumeIsolated {
+                unsafeSelf.contentSize = unsafeSelf.content?.size ?? .zero
+            }
         }
     }
 
@@ -164,12 +167,13 @@ open class TextAttachment: NSTextAttachment, @unchecked Sendable {
             }
 
         case .layer(let layer):
-            syncOnMain {
-                if layer.frame != rect {
-                    layer.frame = rect
+            nonisolated(unsafe) let unsafeLayer = layer
+            MainActor.assumeIsolated {
+                if unsafeLayer.frame != rect {
+                    unsafeLayer.frame = rect
                 }
-                if let textView, layer.superlayer != textView.layer {
-                    textView.layer.addSublayer(layer)
+                if let textView, unsafeLayer.superlayer != textView.layer {
+                    textView.layer.addSublayer(unsafeLayer)
                 }
             }
         default: