Add image compression and improve document edit UI

- Add Swift ImageCompression helper to enforce 200KB limit on iOS
- Update iOS views to use compression for all image uploads
- Fix iOS EditDocumentView to show success only after all uploads complete
- Add AsyncImage thumbnails to Android EditDocumentScreen
- Fix Android success message visibility with delay before state reset
- Add proper error handling for failed image uploads
- Add resetUpdateState on error for consistency

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

composeApp/src/iosMain/kotlin/com/example/mycrib/util/ImageCompressor.ios.kt

@@ -0,0 +1,69 @@
+package com.mycrib.util
+
+import com.mycrib.platform.ImageData
+import kotlinx.cinterop.*
+import platform.Foundation.*
+import platform.UIKit.*
+import platform.posix.memcpy
+
+/**
+ * iOS implementation of image compression
+ * Compresses images to JPEG format and ensures they don't exceed MAX_IMAGE_SIZE_BYTES
+ */
+@OptIn(ExperimentalForeignApi::class)
+actual object ImageCompressor {
+    /**
+     * Compress an ImageData to JPEG format with size limit
+     * @param imageData The image to compress
+     * @return Compressed image data as ByteArray
+     */
+    actual fun compressImage(imageData: ImageData): ByteArray {
+        // Convert ByteArray to NSData
+        val nsData = imageData.bytes.usePinned { pinned ->
+            NSData.create(
+                bytes = pinned.addressOf(0),
+                length = imageData.bytes.size.toULong()
+            )
+        }
+
+        // Create UIImage from data
+        val image = UIImage.imageWithData(nsData) ?: return imageData.bytes
+
+        // Compress with iterative quality reduction
+        return compressImageToTarget(image, ImageConfig.MAX_IMAGE_SIZE_BYTES.toLong())
+    }
+
+    /**
+     * Compress a UIImage to target size
+     */
+    private fun compressImageToTarget(image: UIImage, targetSizeBytes: Long): ByteArray {
+        var quality = ImageConfig.INITIAL_JPEG_QUALITY / 100.0
+        var compressedData: NSData? = null
+
+        while (quality >= ImageConfig.MIN_JPEG_QUALITY / 100.0) {
+            compressedData = UIImageJPEGRepresentation(image, quality)
+
+            if (compressedData != null && compressedData.length.toLong() <= targetSizeBytes) {
+                break
+            }
+
+            quality -= 0.05 // Reduce quality by 5%
+        }
+
+        // Convert NSData to ByteArray
+        return compressedData?.toByteArray() ?: image.let {
+            UIImageJPEGRepresentation(it, ImageConfig.MIN_JPEG_QUALITY / 100.0)?.toByteArray() ?: ByteArray(0)
+        }
+    }
+
+    /**
+     * Convert NSData to ByteArray
+     */
+    private fun NSData.toByteArray(): ByteArray {
+        return ByteArray(this.length.toInt()).apply {
+            usePinned {
+                memcpy(it.addressOf(0), this@toByteArray.bytes, this@toByteArray.length)
+            }
+        }
+    }
+}