Fix replay 2D black canvas and journey UX clarity

Stored analysis overlays now use the decoded frame; latch resets and draw failures surface. Verified with bare-video, replay-wiring, visual_policy, and analysis-progress tests.

apps/studio/config/locales/en_US.json

@@ -218,6 +218,8 @@
     "replay_empty": "No recording open\nPress “Open recording…” below",
     "arrow_empty": "No image yet\nPick a video or camera, then press Run",
     "arrow_empty_tip": "The deformation arrow image appears here while running or previewing",
+    "arrow_render_failed": "Flow arrows could not be drawn for this frame\nTry another view, or reload the video",
+    "arrow_capture_unavailable": "The captured frame is not available for this overlay\nThe raw camera view is still one selection away",
     "depth_unavailable": "No depth data for this frame\n(not a depth of zero, and no silent fallback to the processed image)",
     "depth_scale": "Depth scale {low} – {high}",
     "depth_empty": "This frame's depth is all zeros (0 of {pixels} px non-zero): the ramp's low colour is a real zero response, not missing data",
@@ -448,6 +450,11 @@
     "phase_running": "Acquiring",
     "phase_error": "Error",
     "rail_video_name": "Video file: {name}",
+    "rail_result_profile": "Result profile: {type}",
+    "rail_result_reused": "Stored result",
+    "rail_result_complete": "Analysis complete",
+    "rail_result_running": "Analysing…",
+    "rail_result_ready": "Result ready",
     "data_valid": "Data valid",
     "data_invalid": "{count} invalid sample(s)",
     "calibrated": "Calibrated",
@@ -546,6 +553,10 @@
   },
   "analysis": {
     "title": "Analysing the recording",
+    "title_reused": "Using a stored analysis result",
+    "title_complete": "Analysis complete",
+    "title_cancelled": "Analysis cancelled",
+    "title_failed": "Analysis failed",
     "frames": "{written} / {expected} frames",
     "segment": "segment {index} / {count}",
     "elapsed": "{seconds:.1f} s elapsed",

apps/studio/config/locales/zh_CN.json

@@ -218,6 +218,8 @@
     "replay_empty": "尚未打开录制\n点击下方「打开录制…」",
     "arrow_empty": "尚未采集图像\n请选择视频或摄像机后点击「运行」",
     "arrow_empty_tip": "运行或预览后在此显示形变箭头图",
+    "arrow_render_failed": "本帧无法绘制形变箭头\n请换一种视图，或重新加载视频",
+    "arrow_capture_unavailable": "当前无法取得采集图像用于叠加\n原始相机画面仍可在同一选择器中查看",
     "depth_unavailable": "本帧没有深度数据\n（不是深度为零，也未回退显示普通形变图）",
     "depth_scale": "深度色标 {low} – {high}",
     "depth_empty": "本帧深度全为 0（{pixels} px 中 0 个非零）：色标最低颜色是真实的零响应，不是缺数据",
@@ -448,6 +450,11 @@
     "phase_running": "采集中",
     "phase_error": "出错",
     "rail_video_name": "视频文件： {name}",
+    "rail_result_profile": "结果配置： {type}",
+    "rail_result_reused": "已复用缓存结果",
+    "rail_result_complete": "分析完成",
+    "rail_result_running": "正在分析…",
+    "rail_result_ready": "结果可用",
     "data_valid": "数据有效",
     "data_invalid": "无效样本 {count}",
     "calibrated": "已标定",
@@ -546,6 +553,10 @@
   },
   "analysis": {
     "title": "正在分析录像",
+    "title_reused": "正在使用已缓存的分析结果",
+    "title_complete": "分析完成",
+    "title_cancelled": "分析已取消",
+    "title_failed": "分析失败",
     "frames": "{written} / {expected} 帧",
     "segment": "分段 {index} / {count}",
     "elapsed": "已用 {seconds:.1f} s",