[AZ-895] Deprecate replay auto-sync surface; file AZ-908 follow-up

Option A (minimum-deprecation, 2 SP) per user complexity-budget
decision. Auto-sync stays importable as a raising stub for one cycle
so external callers see a clean ReplayInputAdapterError instead of an
ImportError. Full physical removal is filed as AZ-908 (cycle-5+ backlog).

Production:
- auto_sync.py: 700+ LOC -> 56-line no-op stub raising
  "auto-sync removed; supply --imu CSV instead"
- tlog_video_adapter.py: 700+ LOC -> 105-line deprecated stub;
  ReplayInputAdapter.open() raises immediately, close() is a no-op
- _replay_branch.py: dropped legacy auto-sync branch +
  _build_auto_sync_config; _validate_replay_paths now requires
  imu_csv_path; replay_input_adapter_factory parameter removed
- cli/replay.py: --time-offset-ms / --skip-auto-sync / --auto-trim
  emit DeprecationWarning + stderr line; values ignored
- tlog_replay_adapter.py + tlog_ground_truth.py docstrings: AUDIT-ONLY

Tests:
- DELETED test_az405_auto_sync, test_az405_replay_input_adapter,
  test_az698_window_alignment (covered code no longer runs)
- ADDED test_az895_auto_sync_deprecated_stub (5 parametrised, pins AC-1)
- test_az402_replay_cli: deprecation warnings + ignored-value asserts
- test_az401_compose_root_replay: new imu_csv_path-required gate;
  deleted the calibration-loading test that relied on the removed
  replay_input_adapter_factory injection point
- test_derkachi_real_tlog: xfail reason refreshed to AZ-848 + AZ-883
  (AC-4 "AZ-848-scoped reason")

Docs:
- module-layout.md: replay_input file list flags deprecated modules,
  adds csv_ground_truth.py
- _dependencies_table.md: +AZ-908 row, preamble + totals updated
  (179 -> 180 tasks, 567 -> 570 SP)
- AZ-908 backlog spec added; AZ-895 spec moved todo -> done
- batch_03_cycle4_report.md written

Touched-module tests green (111 passed, 1 skipped). Full unit suite
green: 2287 passed, 85 skipped, 1 deselected (pre-existing flaky perf
test, unrelated).

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/unit/test_az402_replay_cli.py

@@ -114,6 +114,10 @@ def _argv(files: dict[str, Path], **overrides: Any) -> list[str]:
     argv: list[str] = []
     for k, v in base.items():
         argv.extend([k, v])
+    if overrides.get("skip_auto_sync"):
+        argv.append("--skip-auto-sync")
+    if overrides.get("auto_trim"):
+        argv.append("--auto-trim")
     return argv
 
 
@@ -192,12 +196,15 @@ def test_ac3_pace_realtime(
 
 
 # ----------------------------------------------------------------------
-# AC-4: --time-offset-ms forwarded (None when absent)
+# AC-4: --time-offset-ms deprecated (AZ-895) — ignored + warning emitted
 
 
-def test_ac4_time_offset_forwarded(
-    _required_files: dict[str, Path], _airborne_env: None
+def test_ac4_time_offset_ignored_after_az895(
+    _required_files: dict[str, Path],
+    _airborne_env: None,
+    capsys: pytest.CaptureFixture[str],
 ) -> None:
+    """AZ-895: --time-offset-ms is deprecated; value is ignored, warning emitted."""
     # Arrange
     captured: dict[str, Config] = {}
 
@@ -206,13 +213,16 @@ def test_ac4_time_offset_forwarded(
         return 0
 
     # Act
-    rc = replay_cli.main(
-        _argv(_required_files, time_offset_ms=5000), shared_main=fake_main
-    )
+    with pytest.warns(DeprecationWarning, match="--time-offset-ms"):
+        rc = replay_cli.main(
+            _argv(_required_files, time_offset_ms=5000), shared_main=fake_main
+        )
 
     # Assert
     assert rc == EXIT_SUCCESS
-    assert captured["config"].replay.time_offset_ms == 5000
+    assert captured["config"].replay.time_offset_ms is None
+    err = capsys.readouterr().err
+    assert "--time-offset-ms is deprecated (AZ-895)" in err
 
 
 def test_ac4_time_offset_none_when_absent(
@@ -233,6 +243,86 @@ def test_ac4_time_offset_none_when_absent(
     assert captured["config"].replay.time_offset_ms is None
 
 
+def test_az895_skip_auto_sync_ignored_and_warned(
+    _required_files: dict[str, Path],
+    _airborne_env: None,
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    """AZ-895: --skip-auto-sync deprecated; value ignored, warning emitted."""
+    # Arrange
+    captured: dict[str, Config] = {}
+
+    def fake_main(config: Config) -> int:
+        captured["config"] = config
+        return 0
+
+    # Act
+    with pytest.warns(DeprecationWarning, match="--skip-auto-sync"):
+        rc = replay_cli.main(
+            _argv(_required_files, skip_auto_sync=True), shared_main=fake_main
+        )
+
+    # Assert
+    assert rc == EXIT_SUCCESS
+    assert captured["config"].replay.skip_auto_sync_validation is False
+    err = capsys.readouterr().err
+    assert "--skip-auto-sync is deprecated (AZ-895)" in err
+
+
+def test_az895_auto_trim_ignored_and_warned(
+    _required_files: dict[str, Path],
+    _airborne_env: None,
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    """AZ-895: --auto-trim deprecated; value ignored, warning emitted."""
+    # Arrange
+    captured: dict[str, Config] = {}
+
+    def fake_main(config: Config) -> int:
+        captured["config"] = config
+        return 0
+
+    # Act
+    with pytest.warns(DeprecationWarning, match="--auto-trim"):
+        rc = replay_cli.main(
+            _argv(_required_files, auto_trim=True), shared_main=fake_main
+        )
+
+    # Assert
+    assert rc == EXIT_SUCCESS
+    assert captured["config"].replay.auto_trim is False
+    err = capsys.readouterr().err
+    assert "--auto-trim is deprecated (AZ-895)" in err
+
+
+def test_az895_no_deprecated_flags_no_warning(
+    _required_files: dict[str, Path],
+    _airborne_env: None,
+    capsys: pytest.CaptureFixture[str],
+    recwarn: pytest.WarningsRecorder,
+) -> None:
+    """No AZ-895 flag-specific deprecation warning when none of the flags are used."""
+    # Act
+    rc = replay_cli.main(_argv(_required_files), shared_main=lambda _c: 0)
+
+    # Assert
+    assert rc == EXIT_SUCCESS
+    err = capsys.readouterr().err
+    for flag in ("--time-offset-ms", "--skip-auto-sync", "--auto-trim"):
+        assert f"{flag} is deprecated" not in err, (
+            f"unexpected deprecation banner for {flag} when it was not passed"
+        )
+    az895_flag_warnings = [
+        w for w in recwarn.list
+        if issubclass(w.category, DeprecationWarning)
+        and any(
+            f"{flag} is deprecated" in str(w.message)
+            for flag in ("--time-offset-ms", "--skip-auto-sync", "--auto-trim")
+        )
+    ]
+    assert az895_flag_warnings == []
+
+
 # ----------------------------------------------------------------------
 # AC-5: --mavlink-signing-key required (argparse exit 2)