v88 功能增强：产品落盘持久化 + 生图网关适配 + 模板导出优化

- 产品持久化：每完成一个产品立即追加写入 products_pending.jsonl，崩溃不丢已完成产品，finish 读盘合并后统一写模板
- 503 致命错误提前终止：compose/product/seed_shot 端到端识别，提前终止搜索分析，丢弃未完成简报，保留已完成落盘产品直接合成模板
- 模特分配：material_library 合格模特图按任务序号独立随机，同 SPU 多款不再共用同一模特
- 图像网关适配：execution_mode/background 默认不再传入 yunfei 等标准网关，base_url 需带 /v1；429/5xx/空响应退避重试
- Pinterest 分析：删除 term 注入与纯文本降级，失败直接放弃；图片上传前 PIL 完整性校验；suitable_for_print=False 过滤丢弃
- 模板导出：不再产生空白 xlsx，文件名=模板原文件名_已填写；写入前按货号末 3 位升序排序
- 删除对接文档.md，更新 README，gitignore 排除测试产物

graph/nodes/compose_node.py

@@ -12,7 +12,7 @@ import time
 from pathlib import Path
 from typing import Any, Dict, List, Optional
 
-from graph.validate import with_fallback
+from graph.validate import ThreadSafeErrors, with_fallback
 
 RISK_LABEL = {"safe": "✅ 安全", "review": "⚠️ 待复核", "blocked": "⛔ 拦截"}
 
@@ -29,6 +29,18 @@ def _notify_400(on_400, exc) -> None:
         pass
 
 
+def _notify_503(on_503, exc) -> None:
+    """致命图像服务错误（503 / 账户不可用）时触发 on_503 回调（供调用方提前终止任务）。"""
+    if on_503 is None:
+        return
+    try:
+        from graph.pinterest_pipeline import PinterestPipeline
+        if PinterestPipeline.is_fatal_503(exc):
+            on_503()
+    except Exception:  # noqa: BLE001
+        pass
+
+
 def _build_briefs_md(briefs: List[Dict[str, Any]], generated_at: str) -> str:
     lines = [
         "# POD 印花设计简报（LLM 合规筛选 + 生图提示词）",
@@ -112,6 +124,7 @@ def generate_design(ib, brief: Dict[str, Any], design_dir: Path, out_stem: str,
                     errors: List[Dict[str, Any]] = None,
                     seed: Optional[int] = None,
                     on_400=None,
+                    on_503=None,
                     size: str = "1024x1024") -> Optional[str]:
     """生成单张纯印花设计稿（图2）。返回设计稿路径；失败 / 全局 MD5 重复返回 None。
 
@@ -123,6 +136,7 @@ def generate_design(ib, brief: Dict[str, Any], design_dir: Path, out_stem: str,
     无参考图或图生图失败 → 回退 ib.generate() 纯文生图。
     seed: 随机种子（None=不传，网关随机；固定值=可复现，网关支持才生效）。
     on_400: 每次 HTTP 400（且含「内容/图片」）时回调（供调用方累计放弃计数）。
+    on_503: 致命图像服务错误（503/账户不可用）时回调（供调用方提前终止任务）。
     """
     try:
         from graph.style_rules import sanitize_image_prompt, ensure_rebrand_hint
@@ -145,6 +159,7 @@ def generate_design(ib, brief: Dict[str, Any], design_dir: Path, out_stem: str,
             except Exception as e:  # noqa: BLE001
                 print(f"[compose] 图生图（参考图）失败，回退文生图 {brief.get('topic','')}: {e}")
                 _notify_400(on_400, e)
+                _notify_503(on_503, e)
                 out_path = ib.generate(
                     img_prompt, str(design_dir / f"{out_stem}_design.png"),
                     brief.get("composite_negative", ""), size=size, seed=seed)
@@ -161,6 +176,7 @@ def generate_design(ib, brief: Dict[str, Any], design_dir: Path, out_stem: str,
         return out_path
     except Exception as e:  # noqa: BLE001
         _notify_400(on_400, e)
+        _notify_503(on_503, e)
         if errors is not None:
             errors.append({"node": "compose", "type": type(e).__name__,
                            "message": f"设计稿生成失败 {brief.get('topic','')}: {e}", "trace": ""})
@@ -238,12 +254,13 @@ def compose_node(state: Dict[str, Any]) -> Dict[str, Any]:
         def _gen_one(i: int, b: Dict[str, Any]):
             """单张设计稿生成（并发线程内调用，每设计一线程）。"""
             out_path = generate_design(ib, b, design_dir, f"{country}_{i:02d}",
-                                       state.get("errors"), seed=_seed,
+                                       _safe_errors, seed=_seed,
                                        size=compose_cfg.get("design_size", "1024x1024"))
             if out_path is None:
                 return i, b, None, None
             return i, b, out_path, None
 
+        _safe_errors = ThreadSafeErrors()
         targets = [(i, b) for i, b in enumerate(safe_briefs[:design_count], 1)]
         # 并发生成：每张设计一个线程（并行调图像网关），数量多时不串行等待
         workers = max(1, min(len(targets), int((config.get("compose") or {}).get("design_workers", 5))))
@@ -263,6 +280,9 @@ def compose_node(state: Dict[str, Any]) -> Dict[str, Any]:
                     b["design_path"] = out_path
                     designs.append({"topic": b.get("topic", ""), "path": out_path, "design_path": out_path})
                     print(f"[compose] 印花设计稿已生成: {out_path}")
+        # 合并并发线程收集的错误（线程安全收集器 → 主线程统一追加）
+        if len(_safe_errors):
+            state.setdefault("errors", []).extend(list(_safe_errors))
 
     stats = dict(state.get("stats") or {})
     stats["compose"] = {"written": len(briefs), "designs": len(designs), "output_dir": str(output_dir)}