改为按帧自适应显示 Autocal 深度色阶

从有效 UV 区域计算当前帧范围，排除无效值和区域外像素。57 项定向测试及代码、文档检查通过。

apps/autocal/config/locales/en_US.json

@@ -486,7 +486,7 @@
     "arrows": "Displacement arrows",
     "depth": "Depth",
     "depth_tip": "False colour of algorithm depth/deformation, not calibrated millimetres.",
-    "depth_scale": "Deformation colour range 0–1 (algorithm units); values outside saturate",
+    "depth_scale": "Adaptive deformation range for this frame: {low:.4g}–{high:.4g} (algorithm units, not mm)",
     "depth_missing": "No valid depth/deformation for this frame",
     "flow_missing": "No valid displacement for this frame"
   },

apps/autocal/config/locales/zh_CN.json

@@ -486,7 +486,7 @@
     "arrows": "位移箭头",
     "depth": "深度",
     "depth_tip": "显示算法深度／形变信号的伪彩色，不表示已标定的毫米深度。",
-    "depth_scale": "形变伪彩色范围 0–1（算法单位）；超范围颜色饱和",
+    "depth_scale": "形变色阶自动适应本帧：{low:.4g}–{high:.4g}（算法单位，非 mm）",
     "depth_missing": "本帧无有效深度／形变信号",
     "flow_missing": "本帧无有效位移信号"
   },