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/androidMain/kotlin/com/example/mycrib/util/ImageCompressor.android.kt

@@ -0,0 +1,53 @@
+package com.mycrib.util
+
+import android.graphics.Bitmap
+import android.graphics.BitmapFactory
+import com.mycrib.platform.ImageData
+import java.io.ByteArrayOutputStream
+
+/**
+ * Android implementation of image compression
+ * Compresses images to JPEG format and ensures they don't exceed MAX_IMAGE_SIZE_BYTES
+ */
+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 {
+        // Decode the original image
+        val originalBitmap = BitmapFactory.decodeByteArray(
+            imageData.bytes,
+            0,
+            imageData.bytes.size
+        )
+
+        // Compress with iterative quality reduction
+        return compressBitmapToTarget(originalBitmap, ImageConfig.MAX_IMAGE_SIZE_BYTES)
+    }
+
+    /**
+     * Compress a bitmap to target size
+     */
+    private fun compressBitmapToTarget(bitmap: Bitmap, targetSizeBytes: Int): ByteArray {
+        var quality = ImageConfig.INITIAL_JPEG_QUALITY
+        var compressedData: ByteArray
+
+        do {
+            val outputStream = ByteArrayOutputStream()
+            bitmap.compress(Bitmap.CompressFormat.JPEG, quality, outputStream)
+            compressedData = outputStream.toByteArray()
+
+            // If size is acceptable or quality is too low, stop
+            if (compressedData.size <= targetSizeBytes || quality <= ImageConfig.MIN_JPEG_QUALITY) {
+                break
+            }
+
+            // Reduce quality for next iteration
+            quality -= 5
+        } while (true)
+
+        return compressedData
+    }
+}