Add web multimodal image attachments

packages/client/runtime/tests/conversation.spec.ts

@@ -1,22 +1,30 @@
 /** Assistant block classifier (moved here with sessions/conversation.ts). */
 
 import { describe, expect, it } from 'vitest'
+import { AttachmentId } from '@deepseek-ai/dsh-attachment'
 import type { ContentBlock } from '@deepseek-ai/dsh-client-connection/client'
 import { toAssistantBlock, toAssistantBlocks } from '../src/client/sessions/conversation.ts'
 
 describe('toAssistantBlock', () => {
   it('classifies the four block shapes', () => {
+    const attachment = {
+      attachmentId: AttachmentId(`sha256:${'a'.repeat(64)}`),
+      mediaType: 'image/png' as const,
+      bytes: 68,
+      width: 1,
+      height: 1,
+    }
     const blocks: ContentBlock[] = [
       { type: 'text', text: '正文' },
       { type: 'reasoning', text: '思考' },
       { type: 'tool-call', id: 'c1', name: 'echo', arguments: '{}' } as ContentBlock,
-      { type: 'image', data: 'x' } as unknown as ContentBlock,
+      { type: 'image', attachment },
     ]
     expect(toAssistantBlocks(blocks)).toEqual([
       { kind: 'text', text: '正文' },
       { kind: 'reasoning', text: '思考' },
       { kind: 'tool-call', callId: 'c1', name: 'echo', argsRaw: '{}' },
-      { kind: 'other', block: blocks[3] },
+      { kind: 'image', attachment },
     ])
     expect(toAssistantBlock(blocks[0] as ContentBlock)).toEqual({ kind: 'text', text: '正文' })
   })