Extract upload dropzone and queue UI with shared pick validation utils.

frontend/src/utils/upload/analyzePickedUploadFiles.spec.ts

@@ -0,0 +1,38 @@
+import { describe, expect, it } from 'vitest';
+import { analyzePickedUploadFiles } from '@/utils/upload/analyzePickedUploadFiles';
+
+const makeFile = (name: string, type: string, size: number): File =>
+    new File([new Uint8Array(size)], name, { type });
+
+describe('analyzePickedUploadFiles', () => {
+    const maxImageBytes = 100;
+    const maxQueueSize = 2;
+
+    it('accepts images within size and queue limits', () => {
+        const picked = [makeFile('a.png', 'image/png', 50), makeFile('b.jpg', 'image/jpeg', 80)];
+
+        const result = analyzePickedUploadFiles(picked, maxImageBytes, maxQueueSize);
+
+        expect(result.accepted).toHaveLength(2);
+        expect(result.nonImageCount).toBe(0);
+        expect(result.oversizedImagesCount).toBe(0);
+        expect(result.queueOmittedImagesCount).toBe(0);
+    });
+
+    it('skips non-images and oversized files and caps the queue', () => {
+        const picked = [
+            makeFile('doc.pdf', 'application/pdf', 10),
+            makeFile('big.png', 'image/png', 200),
+            makeFile('1.png', 'image/png', 10),
+            makeFile('2.png', 'image/png', 10),
+            makeFile('3.png', 'image/png', 10)
+        ];
+
+        const result = analyzePickedUploadFiles(picked, maxImageBytes, maxQueueSize);
+
+        expect(result.accepted.map(f => f.name)).toEqual(['1.png', '2.png']);
+        expect(result.nonImageCount).toBe(1);
+        expect(result.oversizedImagesCount).toBe(1);
+        expect(result.queueOmittedImagesCount).toBe(1);
+    });
+});