Refactor documentation to replace the Validation Harness with a separate E2E Test Suite, updating references throughout various documents. Adjust the autodev state to reflect the transition from the Decompose phase to the Implement phase, and revise the architecture documentation to clarify system boundaries and component relationships. Enhance risk mitigation documentation to specify affected components and update the component overview diagram accordingly.

_docs/02_tasks/todo/AZ-228_basalt_vio_adapter.md

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+# BASALT VIO Adapter
+
+**Task**: AZ-228_basalt_vio_adapter
+**Name**: BASALT VIO Adapter
+**Description**: Wrap BASALT as a replaceable relative VIO component with health and error behavior.
+**Complexity**: 5 points
+**Dependencies**: AZ-221_shared_geometry_time_sync, AZ-222_runtime_config_errors_telemetry, AZ-223_camera_ingest_calibration, AZ-224_mavlink_gcs_gateway
+**Component**: BASALT VIO Adapter
+**Tracker**: AZ-228
+**Epic**: AZ-213
+
+## Problem
+
+The safety wrapper needs relative VIO state from calibrated frames and FC IMU without inheriting BASALT-specific internals.
+
+## Outcome
+
+- BASALT initialization, processing, and health behavior are exposed through a replaceable adapter.
+- Tracking loss and timestamp mismatch are explicit.
+- The adapter never emits WGS84 coordinates or safety decisions.
+
+## Scope
+
+### Included
+- Initialization and runtime health.
+- Frame + IMU processing behavior.
+- Relative pose/velocity/bias output and quality metadata.
+- Native bridge boundary.
+
+### Excluded
+- Absolute anchor fusion and covariance authority.
+- Satellite matching fallback implementation.
+
+## Dependencies
+
+### Document Dependencies
+- `_docs/02_document/contracts/shared/runtime_contracts.md`
+- `_docs/02_document/contracts/shared/geometry_time_sync.md`
+- `_docs/02_document/contracts/shared/config_errors_telemetry.md`
+
+## Acceptance Criteria
+
+**AC-1: VIO state emitted**
+Given synchronized frame and IMU samples
+When processing succeeds
+Then a relative VIO state packet with tracking quality is emitted.
+
+**AC-2: Timestamp mismatch is explicit**
+Given frame/IMU timestamps are inconsistent
+When processing is requested
+Then the adapter rejects the packet with a timestamp mismatch error.
+
+**AC-3: Health is observable**
+Given initialization or tracking quality changes
+When health is requested
+Then the adapter reports current VIO readiness and degradation state.
+
+## Non-Functional Requirements
+
+**Performance**
+- Adapter processing must be profiled against Jetson latency/memory limits.
+
+**Reliability**
+- BASALT failures are surfaced, not hidden.
+
+## Unit Tests
+
+| AC Ref | What to Test | Required Outcome |
+|--------|--------------|------------------|
+| AC-1 | Valid synchronized packet | VIO state emitted |
+| AC-2 | Bad timestamp window | Explicit error |
+| AC-3 | Tracking loss | Health reports degraded |
+
+## Blackbox Tests
+
+| AC Ref | Initial Data/Conditions | What to Test | Expected Behavior | NFR References |
+|--------|-------------------------|--------------|-------------------|----------------|
+| AC-1 | Derkachi/public replay | Relative VIO path | Continuous estimates where data supports it | Performance |
+
+## Constraints
+
+- BASALT is not the safety authority.
+- GPL VIO dependencies remain reference-only unless explicitly approved.
+
+## Risks & Mitigation
+
+**Risk 1: Nadir fixed-wing fit**
+- *Risk*: BASALT underperforms on low-parallax terrain.
+- *Mitigation*: Representative replay and reference comparisons gate acceptance.