[autodev] Step 13 partial: helpers 1-4 cycle-1 doc sync

Batch 5a of the cycle-1 doc sync. For each of the four
foundation helpers (imu_preintegrator, se3_utils,
lightglue_runtime, wgs_converter):

- Append "Cycle-1 operational reality" section to the
  existing common-helpers/<NN>_*.md, documenting what the
  shipped implementation actually exposes vs. the design-
  intent sketch (interfaces, exception types, public
  constants, AZ-task lineage).

Specific cycle-1 facts captured per helper:

- imu_preintegrator (AZ-276): make_imu_preintegrator
  factory, BMI088-class noise defaults, single
  ImuPreintegrationError exception, actual return type is
  PreintegratedCombinedMeasurements (consumer builds the
  CombinedImuFactor), destructive reset_with_bias semantics,
  first-sample-not-integrated dt=0 handling.
- se3_utils (AZ-277): SE3 = gtsam.Pose3 re-export,
  Se3InvalidMatrixError, strict caller-orthogonalisation
  invariant, _DEFAULT_ROT_ATOL=1e-6 and small-angle Taylor
  cutoff for exp_map, is_valid_rotation predicate, strict
  dtype=float64 everywhere.
- lightglue_runtime (AZ-278 / R14 fix): EngineHandle
  Protocol-typed constructor, LightGlueRuntimeError +
  LightGlueConcurrentAccessError, non-blocking concurrent-
  access guard (raises rather than serialises),
  match_batch equal-length precondition, composition-root
  single-instance into C2.5 + C3.
- wgs_converter (AZ-279 + AZ-490): WEB_MERCATOR_MAX_LAT_DEG
  and MAX_ZOOM constants, WgsConversionError, ECEF arrays
  are ndarray(3,) float64, new horizontal_distance_m method
  (AZ-490 takeoff-origin bounded-delta gate), slippy-map
  tile math hand-rolled to match satellite-provider on-disk
  layout.

Two contract files (imu_preintegrator.md and
wgs_converter.md) need follow-up minor revisions to match
shipped surface; queued for the next contracts-folder
sweep, noted inline in each helper's new section.

Also refresh D-CROSS-CVE-1 opencv-pin leftover replay
timestamp (8-min debounce — gtsam upstream state cannot
change in that window).

Bumps _docs/_autodev_state.md sub_step detail.

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

_docs/02_document/common-helpers/03_helper_lightglue_runtime.md

@@ -28,3 +28,20 @@ class LightGlueRuntime:
 ## Caveats
 
 - The features fed in MUST come from the same backbone as the LightGlue engine was trained for (DISK in production-default; ALIKED / XFeat in alternates). Mixing backbones is a runtime error caught by the matcher's input shape check.
+
+## Cycle-1 operational reality
+
+The shipped surface in `src/gps_denied_onboard/helpers/lightglue_runtime.py` (AZ-278) is the structural fix for R14 (re-rank vs. matcher double-load of the LightGlue engine). Composition root wires ONE `LightGlueRuntime` instance and constructor-injects it into both C2.5 (`InlierBasedReranker`) and C3 (`CrossDomainMatcher`).
+
+- **Constructor** — `LightGlueRuntime(engine_handle: EngineHandle)`. `EngineHandle` is a `Protocol` from `_types/manifests.py` (descriptor_dim, forward(...)) — Layer 1 helper invariant means we do NOT import `gps_denied_onboard.components.*`. C7's `InferenceRuntime.deserialize_engine(LIGHTGLUE_ENGINE_CACHE_ENTRY)` returns the concrete handle at takeoff; the composition root passes it in.
+- **Construction guards** — `LightGlueRuntimeError` is raised for: `engine_handle is None`; `engine_handle` missing the `descriptor_dim` Protocol attribute; `descriptor_dim < 1`.
+- **Descriptor-dim mismatch** — both `match` and `match_batch` validate every `KeypointSet.descriptors` against the engine's `descriptor_dim` and raise `LightGlueRuntimeError` on mismatch (catches "DISK features fed into an ALIKED-trained LightGlue" regressions).
+- **Concurrent-access guard is non-blocking** — the runtime owns a `threading.Lock` but never `.acquire(blocking=True)`. Concurrent entry raises `LightGlueConcurrentAccessError` immediately rather than serialising. This is intentional: if you see this exception, the composition root wired the runtime into more than one thread by mistake — fix the composition, do NOT add blocking serialisation. The lock guards the body of both `match` and `match_batch`; `descriptor_dim()` is lock-free.
+- **`match_batch` equal-length precondition** — `LightGlueRuntimeError` if `len(features_a_list) != len(features_b_list)`. Iteration uses `zip(..., strict=True)`. Indexed validation labels (`features_a_list[i]`) so a downstream test failure points to the offending pair.
+- **`descriptor_dim()` accessor** — returns the engine's descriptor dim as a plain `int` (cached on construction so per-call overhead is one attribute lookup).
+- **Public exceptions** — `LightGlueRuntimeError` (construction / descriptor-dim mismatch / batch-length mismatch) and `LightGlueConcurrentAccessError` (composition-root violation). Both subclass `RuntimeError`.
+
+### Cycle-1 task lineage
+
+- AZ-278 — initial helper, contract producer.
+- R14 structural fix: composition-root single-instance injection into C2.5 + C3 lands in `runtime_root/airborne_bootstrap.py` (the `lightglue_runtime` pre-constructed key consumed by both `_C2_5_STRATEGIES` and `_C3_STRATEGIES`).