为二维与三维深度色标增加每帧自适应选项。

默认仍锁定本会话首帧，勾选后两视图按当前帧有效深度共用同一范围。已用深度色标与显示设置测试验证。

apps/studio/config/locales/en_US.json

@@ -230,6 +230,8 @@
     "arrow_area_masked": "Valid area",
     "arrow_area_full": "Full frame",
     "depth_scale_tip": "Fixed for this session: the range is latched to the first frame that carried depth so frames stay comparable. Grey marks samples with no depth.",
+    "depth_scale_tip_adaptive": "Per-frame adaptive scale: the range follows this frame's valid depth, and the 2D and 3D views share it. Grey marks samples with no depth.",
+    "depth_scale_tip_fixed": "Fixed scale: both the 2D and 3D views use the bounds typed in settings. Grey marks samples with no depth.",
     "plots": "Force Charts",
     "cal": "Calibration",
     "mesh3d": "3D mesh",
@@ -518,14 +520,16 @@
     "legend_fixed": "fixed",
     "scale": "Colour scale",
     "scale_range": "Range",
-    "scale_range_tip": "Bounds of the colour scale in fixed mode. In automatic mode the range comes from the valid samples of the frame on screen, so a quantity whose size differs by orders of magnitude is still readable.",
+    "scale_range_tip": "Bounds used when the colour scale is fixed. In automatic mode the depth scale stays latched to the first frame of the session, unless Per-frame adaptive is on — then both the 2D and 3D views refit to the current frame's valid depth.",
+    "depth_adaptive": "Per-frame adaptive",
+    "depth_adaptive_tip": "When on, the 2D depth view and the 3D surface both refit the colour scale to the current frame's valid depth. When off, the scale stays latched to the first depth frame of the session so frames stay comparable. This switch does nothing while the colour scale is fixed.",
     "scale_fixed": "Fixed",
     "scale_auto": "Automatic",
     "max_fps": "Display rate",
     "max_fps_tip": "How many frames per second the 3D view draws. A display budget only: the camera and the recording are unaffected, and a dropped frame here is never a dropped sample.",
     "reset_view": "Reset view",
     "settings_title": "3D display settings",
-    "settings_hint": "Everything here affects the 3D view's display only: measuring, recording and the charts are untouched, and each change applies at once.",
+    "settings_hint": "Per-frame adaptive applies to both the 2D depth view and the 3D surface. Every other item affects the 3D display only. Measuring, recording and the charts are untouched, and each change applies at once.",
     "legend": "{quantity} [{unit}] · {quality}",
     "legend_none": "No measurement on screen — the surface model is shown uncoloured",
     "quality_calibrated": "calibrated",