[AZ-698] Tlog trim + mid-flight alignment for replay

Adds find_aligned_window cross-correlation (NCC, per-window unit norm)
between IMU energy and video optical-flow magnitude. Returns
AlignedWindow{tlog_start_ns, tlog_end_ns, offset_ms, confidence,
used_fallback}, with fallback to head-takeoff on low confidence to
preserve AZ-405 behavior. TlogReplayFcAdapter honors tlog_start_ns and
skips pre-window messages. New --auto-trim CLI flag, mutex with
--time-offset-ms. AC-1..AC-4 covered by unit tests; AC-5 skipped (no
real flight_derkachi.mp4 in repo). 106 tests pass in regression slice.
Zero new mypy --strict errors.

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

src/gps_denied_onboard/replay_input/__init__.py

@@ -21,6 +21,7 @@ path.
 
 from gps_denied_onboard.replay_input.errors import ReplayInputAdapterError
 from gps_denied_onboard.replay_input.interface import (
+    AlignedWindow,
     AutoSyncConfig,
     AutoSyncDecision,
     ReplayInputBundle,
@@ -33,6 +34,7 @@ from gps_denied_onboard.replay_input.tlog_ground_truth import (
 from gps_denied_onboard.replay_input.tlog_video_adapter import ReplayInputAdapter
 
 __all__ = [
+    "AlignedWindow",
     "AutoSyncConfig",
     "AutoSyncDecision",
     "ReplayInputAdapter",