feat: add Java JRXML-to-PNG rendering pipeline with pixel-level SSIM comparison

- lib/java/: Java renderer (JrxmlRenderer) using JasperReports 6.21.0
  - JrxmlDebug for diagnostics, JrxmlGen for format reference
  - download_jars.sh for one-time dependency setup
- agent/nodes.py: _render_jrxml_to_png() and _compute_pixel_similarity()
  - Pixel comparison integrates into validate node (SSIM < 0.4 fails)
  - Pixel fidelity context injected into correct_jrxml for targeted fixes
- tests/test_pixel_comparison.py: 15 unit tests (render, SSIM, integration)
- .gitignore: exclude lib/java/*.jar, lib/java/*.class, tmp/
- CLAUDE.md: v11 changelog documenting the rendering pipeline
- All non-LLM tests pass (97/97)

frontend/src/App.vue

@@ -70,6 +70,7 @@ async function handleSend(text: string, files: File[]) {
           jrxml_length: data.jrxml_length,
           error_msg: data.error_msg,
           natural_explanation: data.natural_explanation,
+          consult_answer: data.consult_answer,
           retry_count: data.retry_count,
           total_duration_ms: data.total_duration_ms,
           ocr_extraction_result: data.ocr_extraction_result,
@@ -88,8 +89,12 @@ async function handleSend(text: string, files: File[]) {
             type: 'error',
           })
         } else if (data.intent === 'consult_question') {
-          if (streamContent) {
-            chat.addMessage({ role: 'assistant', content: streamContent, type: 'consult' })
+          // 咨询回答：优先用 streamContent，其次用 consult_answer
+          const answerText = streamContent || data.consult_answer || ''
+          if (answerText) {
+            chat.addMessage({ role: 'assistant', content: answerText, type: 'consult' })
+          } else {
+            chat.addMessage({ role: 'assistant', content: '咨询已完成，但未获取到回答内容。', type: 'error' })
           }
         } else {
           if (streamContent) {