feat: 新增52号发际线接口并限制GPU worker来源IP

保留5号历史三档实现，新增中下庭高度定位、扶正裁切、矩形叠加与30案例对比页。

worker仅允许本机和配置白名单访问；网关不增加IP限制。空图片URL字段改写限定为52号，保持旧接口兼容。同步接口、裁切与部署文档。

验证：113项测试通过；1项历史数值基线失败，在未修改的a3fddbb版本复现。浏览器验证5/52及30案例对比页通过。

hairline/service.py

@@ -22,6 +22,7 @@ from .lift_3d import lift_hairline_to_3d, build_middle_row, assemble_full
 from .render import load_ext_mesh, load_texture_rgba, render_hairline_overlay, build_overlay_layer
 from .mask import build_inpaint_mask, compose_comfy_rgba, mask_from_curve
 from .marker_detect import detect_marker_hairline, path_to_curve_mask
+from .height_rule import height_target, clean_curve, place_curve, inpaint_from_curve
 
 import base64
 import io
@@ -178,7 +179,7 @@ def extract_502(image_bgr: np.ndarray):
     return ctx["points"], ctx["valid"]
 
 
-def extract_context(image_bgr: np.ndarray):
+def extract_context(image_bgr: np.ndarray, landmarks: np.ndarray | None = None):
     """照片(BGR) → {landmarks, parse_map, points, valid}。无人脸返回 None。
 
     发际线几何使用射线检测 + 人脸对应点对齐 + 头部轮廓钳制：
@@ -189,7 +190,8 @@ def extract_context(image_bgr: np.ndarray):
     fallback 点不会再跑出头部轮廓。
     """
     rgb = cv2.cvtColor(image_bgr, cv2.COLOR_BGR2RGB)
-    landmarks = get_landmarker().detect(rgb)
+    if landmarks is None:
+        landmarks = get_landmarker().detect(rgb)
     if landmarks is None:
         return None
     parse_map = get_parser().parse(rgb)
@@ -538,6 +540,79 @@ def generate_hairline_pngs(image_bgr: np.ndarray, gender: str,
     return {"images": images, "best_centers": best_centers}
 
 
+def generate_hairline_pngs_52(image_bgr: np.ndarray, gender: str,
+                           hair_styles: list[int], use_mask: bool = True,
+                           prompt: str | None = None,
+                           generate_grow_image: bool = True,
+                           height_reference: dict | None = None,
+                           compare_rules: bool = False,
+                           precomputed_landmarks: np.ndarray | None = None):
+    """接口52：每种 middle 曲线中点对齐到眉心上方 (中庭+下庭)/2。
+
+    只读取 middle 贴图，high/low 保留空值。生发直接复用移动后的预览曲线，
+    不再使用位置不同的黑模板。compare_rules 仅为调试页附带旧规则叠图。
+    接口2仍使用原有管线。
+    """
+    if gender not in ("male", "female"):
+        raise ValueError(f"gender 必须是 male/female，收到 {gender!r}")
+    if not hair_styles:
+        raise ValueError("hair_styles 必填且不能为空")
+    ctx = extract_context(image_bgr, landmarks=precomputed_landmarks)
+    if ctx is None:
+        return None
+    h, w = image_bgr.shape[:2]
+    uv, ext_faces = load_ext_mesh()
+    rule = height_target(ctx["landmarks"], w, h, height_reference)
+    textures = get_texture_map()[gender]
+
+    # use_mask=False：干净原图+空遮罩与贴图无关，只跑一次 ComfyUI，选中项复用
+    # generate_grow_image=False：完全跳过生发（最耗时），grown_png 恒为 None
+    shared_grown = None
+    if generate_grow_image and not use_mask:
+        shared_grown = _grow_from_texture(image_bgr, ctx, None, use_mask=False, prompt=prompt)
+
+    images, best_centers = [], None
+    for s in hair_styles:  # s = 1-indexed 发型序号
+        key, mid_path = textures[s - 1]
+        old = build_overlay_layer(h, w, ctx["points"], ext_faces, uv, load_texture_rgba(mid_path))
+        overlay, placement = place_curve(old, rule["target_center"], ctx["landmarks"])
+        overlays = {"middle": overlay, "high": None, "low": None}
+        if not generate_grow_image:
+            grown_png = None
+        elif not use_mask:
+            grown_png = shared_grown
+        else:
+            grown_png = None
+            try:
+                marked, mask = inpaint_from_curve(
+                    image_bgr, ctx["landmarks"], ctx["parse_map"], overlay)
+                buf = io.BytesIO()
+                compose_comfy_rgba(marked, mask).save(buf, format="PNG", compress_level=1)
+                grown_png = comfyui.run(buf.getvalue(), prompt=prompt)
+            except Exception as ex:  # 单张生发失败不丢弃设计曲线
+                logger.warning("接口52 生发失败 type=%s：%s", key, ex)
+        # Flux may round dimensions to a multiple of its latent stride.
+        # Restore the input size so the preview and generated photo align.
+        if grown_png:
+            grown_png = _upscale_png_to(grown_png, w, h)
+        item = {"hairline_type": key, "order": s, "overlays": overlays,
+                "grown_png": grown_png, "height_placement": placement}
+        if compare_rules:
+            item["legacy_overlay"] = clean_curve(old)
+        images.append(item)
+        if best_centers is None:
+            center = placement["new_center"]
+            best_centers = {"middle": (round(center["x"]), round(center["y"])),
+                            "high": None, "low": None}
+    guide_landmarks = {
+        str(index): {"x": float(ctx["landmarks"][index, 0] * w),
+                     "y": float(ctx["landmarks"][index, 1] * h)}
+        for index in (9, 150, 152, 162, 251, 389)
+    }
+    return {"images": images, "best_centers": best_centers, "height_rule": rule,
+            "guide_landmarks": guide_landmarks}
+
+
 # 接口3 送 ComfyUI 前限边，降低峰值显存，避免与接口2 切换时把 Flux 挤出。
 # 统一 prompt 后 Flux 不再被 CLIP 挤出，接口3 可用较高分辨率。可用 GROW_B_MAX_SIDE 覆盖。
 _GROW_B_MAX_SIDE = int(os.getenv("GROW_B_MAX_SIDE", "1024"))