Revise acceptance criteria and restrictions documentation to clarify recent updates and specifications. Key changes include enhanced definitions for position accuracy, image processing quality, and operational parameters, as well as updates to camera specifications and validation requirements. This revision aims to improve clarity and ensure alignment with project goals.

_docs/02_document/common-helpers/02_helper_time_sync.md

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+# Time Sync Helper
+
+## Purpose
+
+Shared timestamp validation and alignment utilities for frame, IMU, telemetry, FDR, and replay data.
+
+## Responsibilities
+
+- Monotonic timestamp checks.
+- Frame-to-IMU window selection.
+- Clock-domain conversion metadata.
+- Replay ordering validation.
+- Gap and jitter metrics.
+
+## Non-Responsibilities
+
+- No VIO state estimation.
+- No MAVLink parsing beyond normalized timestamp fields.
+- No recovery policy; callers decide whether to degrade or reject.
+
+## Consumers
+
+| Component | Usage |
+|-----------|-------|
+| Camera ingest/calibration | Frame ordering and timestamp metadata |
+| BASALT VIO adapter | IMU/frame synchronization |
+| MAVLink/GCS integration | Telemetry timestamp normalization |
+| FDR/observability | Segment ordering |
+| Validation harness | Fixture validation |