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",