Browse a long recording from disk instead of loading it into memory

What
- record/index.py: RecordingIndex streams forces.csv once and keeps only the
  small things — one time, one validity flag, one frame id per row plus a byte
  offset every 4096 rows (~6.5 MB per 500k rows). row_range() bisects the times,
  read_rows() seeks to the nearest checkpoint and scans forward, and overview()
  folds every row into its bucket during the same pass to build a per-axis
  min/max envelope.
- read_rows(max_points, unit) decimates **while streaming**: each bucket keeps
  the extreme row of every axis in the requested unit, so a long interval never
  has to exist in memory in full and a shear spike survives a flat normal channel.
- RecordingReader: info() decimates above max_rows (default 200k) and marks
  itself decimated, with total_rows and a duration taken from the frame index
  rather than from the view; window()/window_all()/overview()/statistics() read
  the interval being asked about. list/window semantics unchanged for small
  recordings.
- force/source.py: StoreCurveSource (live memory) and RecordingCurveSource (disk
  interval + cached envelope) implement one interface — extent, window,
  envelope, statistics, duration_s — so ForcePlotsPanel asks a *source* instead
  of knowing where the data lives.
- force_plots: reads through the source (window, envelope, statistics, extent),
  which also replaces its last direct store accesses.
- playback_dialog: draws the whole-session view through window_all() in the unit
  being shown (bounded by CHART_MAX_POINTS), and says so when the view is
  decimated ("显示 N / 共 M 行") instead of letting the operator count points.
- experiment._run: a failure that lands while the files are opening can no longer
  be overwritten by the writer's own transition to "recording" (found by a flaky
  test; the state check now covers STATE_FAILED).

Why
The store releases old blocks above ~4.6 h and the replay loaded every CSV row
into Python lists before drawing anything, so neither the live browser nor the
replay could show an earlier interval of a long recording. The index makes the
disk the data source and memory a cache of what is on screen.

Verification
- shared/tests/test_history_source.py (new, 8 cases) over a 12 000-row recording:
  the index reports its rows and reads a bounded interval; a large recording is
  marked decimated with its true duration and total rows; a small one is not; an
  interval read sees the exact rows including a single peak; a decimated window
  keeps the peak; the envelope fits the whole session in ≤200 points, keeps the
  spike and is cached; the disk and memory sources agree on extent, values and
  statistics; the whole session can be read without holding it all. Shared
  suites: 146 tests, 0 failures (three consecutive runs).
- apps/studio/tools/ui_check.py: the replay section now checks the index row
  count, that an interval read spans only the interval, the envelope size and
  total_rows. 324 checks, 0 failures.
- apps/studio/tests/test_ui_smoke.py: 43 tests, 36 pass; the 7 failures are the
  unchanged sandbox/harness artifacts.
- D:/orisys_ws/_review_phase12/reproduce.py: all ten lines unchanged;
  compileall, locale and prefs parity clean.
- apps/studio/docs/record-channel.md §8 documents the index, the reader API and
  the unified source, and lists what is still hardware work.

Not in this change
- Maximum RSS / backlog / loss measurements at real resolution on the target ARM
  board (needs the hardware), and range CSV export.

apps/studio/config/locales/en_US.json

@@ -115,6 +115,8 @@
     "box_zoom_tip": "Switch to rubber-band zoom (drag a region on the chart)",
     "selection": "Selection {duration}s / {samples} samples — {detail}",
     "selection_empty": "No valid samples in the selection",
+    "value_unavailable": "n/a",
+    "value_unavailable_tip": "No curve is loaded for {channel}, so it has no value in this unit (raw counts are never shown in its place)",
     "browse_only_tip": "Drag or scroll on the chart to browse history"
   },
   "layout": {
@@ -154,14 +156,21 @@
     "depth_state_approximate": "No reset or pre-roll history for this segment: the algorithm state is an approximation",
     "depth_warnings": "Recomputation notes: {detail}",
     "warnings": "Replay notes: {detail}",
+    "decimated": "This recording is long, so the curves are a decimated view ({shown} of {total} rows; intervals are read from disk on demand)",
     "warn_config_changed": "the config differs from recording time, so the recomputed depth may differ",
     "warn_sdk_changed": "the SDK version differs from recording time, so the recomputation may differ",
     "warn_config_missing": "no config hash was recorded, so recomputation cannot be verified",
     "warn_depth_recomputed": "depth comes from offline recomputation, not from stored data",
     "warn_rows_skipped": "some unparsable CSV rows were skipped",
     "warn_frames_dropped": "frames were lost to a full queue; only their index rows remain (shown as \"not recorded\")",
+    "warn_out_of_order": "this recording was written by an older version: its rows are not in time order, so the replay re-sorts them and window edges may differ",
     "warn_state_across_segment": "the algorithm state cannot be carried across a segment",
-    "warn_state_approximate": "the algorithm state is an approximation"
+    "warn_state_approximate": "the algorithm state is an approximation",
+    "warn_state_approximate_after_rewind": "the video was reopened to reach an earlier frame, so the state may differ",
+    "warn_state_too_far_back": "the zeroing is too far back: reading there would exceed the replay budget, so the state is approximate",
+    "warn_reset_frame_not_indexed": "the zeroing frame is not in the frame index, so the state cannot be rebuilt from it",
+    "warn_reset_frame_not_in_video": "the zeroing frame never reached the video, so the state cannot be rebuilt from it",
+    "warn_reset_not_applied": "the replay could not re-apply the zeroing, so the state may differ"
   },
   "record": {
     "label": "Record",
@@ -177,6 +186,8 @@
     "start_failed": "Could not start recording: {error}",
     "finished": "Recording finished — {frames} frames / {segments} segment(s) in {path}",
     "finished_with_problems": "Recording finished with problems: {detail}",
+    "closing": "Closing the recording files…",
+    "failed_state": "The recording failed (see the summary and the log)",
     "alarm": "Recording problem: {detail}"
   },
   "cal": {
@@ -204,8 +215,12 @@
     "open_record_tip": "Reopen a saved calibration session to inspect every point's samples and diagnostics",
     "open_record_filter": "Calibration records (*.json)",
     "open_record_ok": "Loaded {path} ({points} point(s))",
+    "open_record_device": "Recorded on: {device}",
     "open_record_warnings": "Note: {detail}",
     "open_record_failed": "Could not open the calibration record: {error}",
+    "apply_mismatch_title": "Calibration does not match the target device",
+    "apply_mismatch": "This coefficient file belongs to: {device}\nMismatch: {detail}\n\nCurrent target: {sensor_type} / {config}\n\nApplying it would load coefficients that were not measured on this device.",
+    "apply_mismatch_skipped": "Apply cancelled (the calibration belongs to another device)",
     "sn": "SN",
     "sn_placeholder": "Serial number (optional)",
     "live_raw_label": "Live raw",
@@ -255,11 +270,13 @@
     "export_local": "Also wrote {path}",
     "export_warnings": "Skipped: {detail}",
     "export_failed": "Export failed: {error}",
+    "export_no_model": "Nothing to export: {detail}",
     "apply_title": "Apply calibration",
     "apply_confirm": "Apply the calibration just exported to the current device?\n\nSensor type: {sensor_type}\nConfig: {config}\n\nChoosing No keeps the exported file and leaves the running device untouched.",
     "apply_skipped": "Exported; not applied to the device",
     "apply_pending": "Requested calibration for {sensor_type}; waiting for the device to confirm…",
     "applied": "Device confirmed the calibration is in effect (version {version})",
+    "applied_none": "Device confirmed: no calibration is loaded (the column stays empty)",
     "export_only": "Exported coefficients to {path} (not applied to the device)",
     "apply_no_target": "No device to apply to (run an acquisition first)"
   },
@@ -286,6 +303,7 @@
     "video_ended": "Video ended",
     "camera_disconnected": "Camera disconnected",
     "reset_ok": "Tracker reset",
+    "reset_pending": "Zeroing requested; waiting for the acquisition thread to confirm…",
     "finger_run_unavailable": "Run is not available for this sensor type",
     "video_required": "Select a video file first",
     "config_missing": "Sensor config not found for {type}",