# Batch 05 — Cycle 1 Implementation Report

**Date**: 2026-05-11
**Batch shape**: finish cross-cutting (config precedence tests + 3 Layer-1 helpers)
**Tasks**: AZ-271, AZ-282, AZ-276, AZ-278 (10 complexity points)
**Verdict**: PASS_WITH_WARNINGS (see `reviews/batch_05_review.md`)

## What landed

### AZ-271 — Config precedence unit tests

- `tests/unit/shared/config/test_precedence.py` — 6 tests verifying
  env > YAML > defaults precedence for ≥3 keys per layer plus
  multi-file YAML merge order. The `_layer_msg` helper standardises
  AC-5 assertion messages so failures name the offending layer.

### AZ-282 — RansacFilter helper

- `src/gps_denied_onboard/helpers/ransac_filter.py` — static-only
  `RansacFilter`, frozen `RansacResult`, `RansacFilterError`.
  Determinism enforced by `cv2.setRNGSeed(0)` immediately before every
  `findHomography(..., RANSAC)` call.
- `tests/unit/test_az282_ransac_filter.py` — 16 tests (10 ACs +
  parametrised distortion shape contract + frozen dataclass + SE3
  alias).

### AZ-276 — ImuPreintegrator helper

- `src/gps_denied_onboard/helpers/imu_preintegrator.py` —
  `ImuPreintegrator` wraps GTSAM `PreintegratedCombinedMeasurements`;
  factory `make_imu_preintegrator(calibration)` reads optional IMU
  noise model from `CameraCalibration.metadata["imu_noise_model"]`,
  defaulting to documented BMI088-class densities.
- `src/gps_denied_onboard/_types/nav.py` — adjacent hygiene:
  `ImuSample(ts_ns: int, ...)` and `ImuWindow(ts_start_ns, ts_end_ns)`
  brought into line with the contract; new `ImuBias` dataclass.
- `tests/unit/test_az276_imu_preintegrator.py` — 11 tests covering all
  7 ACs plus `integrate_window`, post-rebias guard, factory return
  type, and the GTSAM `CombinedImuFactor` re-export.

### AZ-278 — LightGlueRuntime helper (R14 structural fix)

- `src/gps_denied_onboard/helpers/lightglue_runtime.py` —
  `LightGlueRuntime(engine_handle)` with descriptor-dim validation +
  non-blocking concurrent-access guard (`Lock(blocking=False)` →
  `LightGlueConcurrentAccessError` on contention).
- `src/gps_denied_onboard/_types/manifests.py` — adjacent hygiene
  (spec-approved): new `EngineHandle` Protocol with `descriptor_dim`
  property + `forward(features_a, features_b) -> CorrespondenceSet`.
- `src/gps_denied_onboard/_types/matching.py` — adjacent hygiene:
  new `KeypointSet` and `CorrespondenceSet` dataclasses.
- `tests/unit/test_az278_lightglue_runtime.py` — 10 tests covering all
  7 ACs plus negative paths (descriptor_dim < 1, mismatched batch
  lengths, accessor parity).

### Dependency-pin change (Finding 1)

- `pyproject.toml` — `opencv-python` pin relaxed from
  `>=4.12.0` to `>=4.11.0.86,<4.12` because gtsam-4.2 (PyPI) is only
  numpy-1.x-ABI-compatible and `opencv-python>=4.12` requires
  numpy-2 at runtime.
- `ci/opencv_pin_gate.py` — `MIN_VERSION` ratchet held at `(4, 11, 0)`.
- `tests/unit/test_ac10_ci_gates.py` — test message updated to
  reference the leftover.
- `_docs/_process_leftovers/2026-05-11_d_cross_cve_1_opencv_pin_deferred.md`
  — full replay procedure + CVE exposure note + owner placeholder.

## Test results

- **Full suite**: 294 passed, 2 skipped (`cmake`, `actionlint` env-skip
  — pre-existing).
- **New in batch 5**: 43 tests (6 + 16 + 11 + 10).
- `ruff check` + `ruff format` clean across all touched files.

## AC coverage

| Task | ACs | Tests | Status |
|------|-----|-------|--------|
| AZ-271 | 5 | 6 | All PASS |
| AZ-282 | 10 | 16 | All PASS |
| AZ-276 | 7 | 11 | All PASS |
| AZ-278 | 7 | 10 | All PASS |

## Schema / dependency changes

- `FdrConfig` — unchanged (batch 4).
- `CameraCalibration` — unchanged; the IMU noise model is read from
  the existing `metadata` field with documented defaults so this is
  additive.
- `_types/nav.py` — **schema change** to `ImuSample` and `ImuWindow`
  (datetime → `ts_ns: int`) plus new `ImuBias`. No production
  consumers depend on the old fields; downstream C1/C5 spec work will
  pick up the new shape via the contracts.
- `_types/manifests.py` — new `EngineHandle` Protocol (additive).
- `_types/matching.py` — new `KeypointSet`/`CorrespondenceSet`
  dataclasses (additive).
- `pyproject.toml` — `opencv-python` pin relaxed (see Finding 1 in the
  review). All other pins unchanged.

## Follow-ups

- **D-CROSS-CVE-1 replay** — pending a numpy-2-compatible gtsam wheel.
  Tracked in `_docs/_process_leftovers/`.
- **NFR-perf budgets** — Tier-2 microbenches deferred to AZ-444
  (Jetson harness). Functional gates are green in this batch.