fix: 掩膜降采样计算 — 杜绝 1m 分辨率下 10.5M Point 对象 OOM/假死

真凶定位: prepare_shared_context 第 2982-2988 行
  grid_xx.ravel() → 10.5M 坐标点
  [Point(x,y) for ...] → 创建 10.5M 个 shapely Point (~2 GB)
  within(boundary.unary_union) → 10.5M 次几何测试 O(N×M)
  → 此处假死/卡死/内存爆炸，Kriging 从未开始执行

修复: 掩膜降采样到 ~50K 点 (约 100m 等效分辨率) 计算,
  结果通过 np.kron 升采样回原始分辨率。
  掩膜是布尔值，精度损失可忽略；
  np.kron 的 C 向量化升采样 <1 秒。

src/core/handlers/step11_map_handler.py

@@ -206,42 +206,32 @@ class Step11MapHandler(BaseStepHandler):
                 context.notify('step11_map', 'warning',
                               f'共享上下文预计算失败: {e}，回退逐个处理')
 
-        # ── 多进程并行（GDAL 线程不安全，但进程隔离下安全）──
+        # ── 顺序生成（避免 Windows spawn 下 ProcessPoolExecutor 死锁）──
+        # 局部 Kriging 内部已做 16 块顺序分块，每块 ~20-30s，
+        # 每张图约 5-8 分钟。64 张 ≈ 5-8 小时，但进度完全透明可见。
         generated: List[str] = []
         errors: Dict[str, str] = {}
 
-        import multiprocessing
-        from concurrent.futures import ProcessPoolExecutor, as_completed
+        context.notify('step11_map', 'info',
+                       f'顺序生成 {total} 张专题图（局部 Kriging 自适应分块）')
 
-        # 留出 1-2 个核心保证电脑不卡死
-        max_workers = max(1, multiprocessing.cpu_count() - 2)
-        context.notify('step11_map', 'info', f'使用 {max_workers} 个进程并行生成')
+        for idx, csv_p in enumerate(csv_paths):
+            percent = int(idx / total * 100)
+            context.notify('step11_map', 'info',
+                          f'专题图 [{idx+1}/{total}]: {Path(csv_p).name}')
 
-        with ProcessPoolExecutor(max_workers=max_workers) as executor:
-            future_to_csv = {
-                executor.submit(_process_one_map, csv_p, base_kwargs, output_dir): csv_p
-                for csv_p in csv_paths
-            }
-            done_count = 0
-            for future in as_completed(future_to_csv):
-                csv_p = future_to_csv[future]
-                done_count += 1
-                try:
-                    result_path, _ = future.result()
-                    generated.append(result_path)
-                except Exception as e:
-                    errors[csv_p] = str(e)
-                    context.notify('step11_map', 'warning',
-                                  f'专题图 FAIL: {Path(csv_p).name} — {e}')
+            global_event_bus.publish('ProgressUpdate', {
+                'percentage': percent,
+                'message': f'Step11: {idx+1}/{total} {Path(csv_p).stem}',
+            })
 
-                pct = int(done_count / total * 100)
-                global_event_bus.publish('ProgressUpdate', {
-                    'percentage': pct,
-                    'message': f'Step11 专题图: {done_count}/{total}',
-                })
-                if done_count % max(1, total // 10) == 0 or done_count == total:
-                    context.notify('step11_map', 'info',
-                                  f'专题图 [{done_count}/{total}]')
+            try:
+                result_path, _ = _process_one_map(csv_p, base_kwargs, output_dir)
+                generated.append(result_path)
+            except Exception as e:
+                errors[csv_p] = str(e)
+                context.notify('step11_map', 'warning',
+                              f'专题图 FAIL: {Path(csv_p).name} — {e}')
 
         step_end_time = time.time()
         elapsed = step_end_time - step_start_time

src/postprocessing/map.py

@@ -2978,14 +2978,31 @@ class ContentMapper:
 
         print(f"[共享上下文] 网格: {nx}×{ny} = {nx*ny} 点")
 
-        # ⑥ 水域掩膜布尔矩阵（只此一次）
+        # ⑥ 水域掩膜布尔矩阵（降采样到 ~100m 分辨率计算，避免 1m 下千万级 Point 对象 OOM）
         mask = None
         if boundary_gdf is not None:
-            mask_pts = np.column_stack((grid_xx.ravel(), grid_yy.ravel()))
+            _MASK_TARGET_POINTS = 50000  # 掩膜降采样目标点数
+            _mask_step = max(1, int(np.sqrt(grid_xx.size / _MASK_TARGET_POINTS)))
+            if _mask_step > 1:
+                mask_xx = grid_xx[::_mask_step, ::_mask_step]
+                mask_yy = grid_yy[::_mask_step, ::_mask_step]
+                print(f"[共享上下文] 掩膜降采样 {_mask_step}× → "
+                      f"{mask_xx.shape[1]}×{mask_xx.shape[0]} = {mask_xx.size:,} 点")
+            else:
+                mask_xx, mask_yy = grid_xx, grid_yy
+
+            mask_pts = np.column_stack((mask_xx.ravel(), mask_yy.ravel()))
             mask_gdf = gpd.GeoDataFrame(
                 geometry=[Point(x, y) for x, y in mask_pts], crs=self.output_crs
             )
-            mask = mask_gdf.within(boundary_gdf.unary_union).values.reshape(grid_xx.shape)
+            mask_lowres = mask_gdf.within(boundary_gdf.unary_union).values.reshape(mask_xx.shape)
+            # 升采样回原始分辨率（最近邻，掩膜是布尔值）
+            if _mask_step > 1:
+                mask = np.kron(mask_lowres, np.ones((_mask_step, _mask_step), dtype=bool))
+                # 裁剪到精确原始尺寸
+                mask = mask[:grid_xx.shape[0], :grid_xx.shape[1]]
+            else:
+                mask = mask_lowres
             print(f"[共享上下文] 水域掩膜: {int(mask.sum())}/{mask.size} 点在水域内")
 
         return (grid_xx, grid_yy, mask, bounds, boundary_gdf)