[AZ-420] Batch 81 housekeeping + cumulative 79-81 review

Archive AZ-420 to done/; add cumulative review for batches 79-81 (PASS,
no new findings); advance autodev state to await batch 82.

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

_docs/03_implementation/reviews/cumulative_79_81_review.md

@@ -0,0 +1,209 @@
+# Cumulative Code Review — Batches 79, 80, 81
+
+**Date**: 2026-05-17
+**Verdict**: PASS
+
+Covers the arc:
+
+* **Batch 79 / AZ-599** — FT-P-02 Derkachi vertical-slice fixture
+  builder + `_common.py` extraction (factored out shared helpers
+  from the b78 FT-P-01 builder).
+* **Batch 80 / AZ-600** — refactor `_common.py` + `build_p01_fixtures.py`
+  + `build_p02_fixtures.py` into a parameterised strategy framework
+  (`builder.py`).
+* **Batch 81 / AZ-420** — FT-P-12 (GCS downsample) + FT-P-13 (GCS
+  command path) scenarios with a new `gcs_telemetry_evaluator.py`
+  helper + `sitl_observer.capture_gcs_tlog`.
+
+The three batches together close two unrelated arcs:
+
+1. **Fixture-builder consolidation**: the b78 FT-P-01 vertical slice
+   landed as a one-off builder; b79 added a second one-off (FT-P-02)
+   plus an `_common.py` extraction; b80 then collapsed both into a
+   strategy-pattern framework where future scenarios compose existing
+   strategies. Net result: a single durable `builder.py` instead of
+   N per-scenario builders.
+2. **GCS-leg blackbox coverage**: b81 adds the FT-P-12 and FT-P-13
+   scenarios that exercise the operator-facing telemetry stream
+   and command path — orthogonal to the fixture-builder work and
+   the first scenario pair that probes the C8 `QgcTelemetryAdapter`.
+
+## Cross-Cutting Themes
+
+### Convergence on a single helper / evaluator shape
+
+Both b80's `builder.py` strategies and b81's
+`gcs_telemetry_evaluator.py` follow the same convention seen across
+the wider runner.helpers package:
+
+1. **Pure-logic dataclasses** (`FixtureBuilderConfig`,
+   `GcsSummaryRateReport`, `HintAckReport`, `SearchRegionShiftReport`,
+   `HintRejectionReport`, `InboundHint`, `FdrCommandAck`,
+   `SearchRegionRecord`) — `@dataclass(frozen=True)` with a `passes`
+   property where the dataclass is an evaluation result.
+2. **`Iterable[TlogMessage]` ingress** — b81's four evaluators all
+   accept `Iterable[TlogMessage]` instead of a Sequence so they
+   compose with `mavproxy_tlog_reader.iter_messages` without
+   materialisation. The scenario test materialises once via
+   `collect_messages_to_list` and reuses for multiple analyzers
+   (mirrors `ap_contract_evaluator.collect_messages_to_list` from b78).
+3. **No `src/gps_denied_onboard` imports** — `e2e/_unit_tests/
+   test_no_sut_imports.py` walks the entire `e2e/` tree and
+   passes across all three batches.
+
+### Fixture-naming convention
+
+The artifact naming pattern `<artifact>_<host>.tlog` is consistent
+across batches:
+
+* `ap_tlog_<host>.tlog` (pre-existing, AP/SITL-side)
+* `gcs_tlog_<host>.tlog` (b81, GCS-side)
+
+Same env var (`E2E_SITL_REPLAY_DIR`), same observer surface
+(`sitl_observer.capture_ap_tlog` / `capture_gcs_tlog`), same
+RuntimeError messaging convention ("RuntimeError: capture_X: env var
+not set", "fixture not found at PATH").
+
+### Strategy-pattern reuse readiness
+
+B80's `builder.py` factored four ABCs (`VideoSource`, `TlogSource`,
+`FdrProjection`) + six concrete impls. B81 was the first scenario
+batch after b80; it consumes no new strategy from `builder.py`
+(FT-P-12/13 are runtime tests, not fixture-builder scenarios), so
+the strategy framework's reuse is still latent. The next builder
+work (any of FT-P-04/05/07/08/10/11) will be the actual test of
+b80's refactor — they should each land as a ~30-line config
+factory, not a new builder module.
+
+## Phase-by-Phase Findings
+
+### Phase 1 — Context Loading
+
+Read all three batch reports, all three per-batch reviews, and the
+task specs AZ-599, AZ-600, AZ-420. Mapped changed files to tasks via
+the batch reports' "Tasks" sections.
+
+### Phase 2 — Spec Compliance (cumulative)
+
+All three per-batch reviews already verified ACs against tests.
+Re-walking AC coverage across the union:
+
+* **AZ-599 (FT-P-02 builder)**: 7 scenario integration tests
+  (test_sitl_replay_builder_p02.py). Behavior preserved through
+  b80's refactor (same tests now in slimmed file, plus new
+  strategy-level coverage in test_sitl_replay_builder_builder.py).
+* **AZ-600 (strategy refactor)**: 33 strategy-level tests + 6 + 7
+  scenario tests = 46 total across the three files.
+* **AZ-420 (FT-P-12+13)**: 39 evaluator + adapter unit tests + 2
+  scenario tests (skip locally; collect 12 param IDs total).
+
+No AC went from covered → uncovered between batches.
+
+### Phase 3 — Code Quality (cumulative)
+
+* **SRP across batches**: b80 splits orchestration (`build_fixtures`)
+  from materialisation (each strategy) — clean. B81's
+  `gcs_telemetry_evaluator.py` keeps four independent evaluator
+  functions in one module — defensible because they all consume
+  the same tlog stream and the same FDR record family; splitting
+  would just shuffle imports.
+* **Naming consistency**: timestamps end in `_us` or `_ms` everywhere;
+  distances end in `_m`; rates end in `_hz`; coordinates end in
+  `_deg`. Units in the name, not in comments. ✓
+* **Test AAA pattern**: spot-checked 10 random tests across all three
+  batches. All use `# Arrange / # Act / # Assert` comments per the
+  coding rules. ✓
+* **No comment narration of mechanics**: only docstrings + one-liners
+  on non-obvious invariants (`STATIONARY_Z_ACCEL_MG` gravity encoding
+  in b80; the greedy-pairing "keep moving forward to find the last
+  pre-hint" in b81). ✓
+
+### Phase 4 — Security Quick-Scan (cumulative)
+
+* No SQL, no `shell=True`, no `eval`/`exec`. ✓
+* No hardcoded secrets/API keys. ✓
+* `subprocess.run` in `builder.py`'s `run_gps_denied_replay` uses a
+  list-form `cmd`, not shell-interpolation. ✓
+* Tlog/FDR record parsing wraps `int()` / `float()` calls with
+  ValueError re-raise messaging on the offending payload (b81's
+  `parse_reloc_payload`, b80's `ImuCsvTlog`). ✓
+
+### Phase 5 — Performance (cumulative)
+
+* `build_fixtures` is bound by subprocess (`run_gps_denied_replay`)
+  wall-clock, not in-process compute. Per-strategy materialisation
+  is O(n) over input rows/frames. ✓
+* `gcs_telemetry_evaluator` is all O(n) over messages with a single
+  O(n log n) ack sort. ✓
+* No new blocking I/O introduced. No new `time.sleep` polling loops. ✓
+
+### Phase 6 — Cross-Task Consistency
+
+* **Interface compatibility across batches**: b80 removed
+  `_common.py`; b81 doesn't reference it. The only b81-side import
+  from the fixture-builder area is the implicit fixture file path
+  pattern, which is unchanged. No drift. ✓
+* **Duplicate symbols**: `compute_gcs_summary_rate` (b81) and
+  `compute_gps_input_rate` (pre-existing
+  `ap_contract_evaluator`) compute the same `(N-1)/window`
+  rate over different message types — same algorithm, different
+  AC. The fact they're separate functions is correct (they have
+  different domain semantics). If a third "rate over message
+  type X" appears, then a generic helper would be warranted. ✓
+* **Shared logging / config**: no batch introduced a new logging or
+  config loader; the existing `runner.helpers.replay_mode` env-var
+  helpers are reused. ✓
+
+### Phase 7 — Architecture Compliance
+
+`_docs/02_document/module-layout.md` declares Blackbox Tests as the
+sole owner of `e2e/**`.
+
+1. **Layer direction**: all imports across the 23 changed files
+   resolve within `e2e/` (`runner.helpers.*`, `e2e.fixtures.*`,
+   stdlib, pytest, mavlink/pymavlink, cv2 in the b80 builder). No
+   imports of `src/gps_denied_onboard.*`. ✓
+2. **Public API respect**: all cross-helper imports go through
+   module-level public names; no `_private` symbol crossed a module
+   boundary. ✓
+3. **No new cyclic deps**: b80's `builder.py` is a leaf consumed by
+   `build_p01_fixtures.py` and `build_p02_fixtures.py`; b81's
+   `gcs_telemetry_evaluator.py` is a leaf consumed by the two
+   scenario tests. No back-edges. ✓
+4. **No duplicate symbols across components**: there is only one
+   component touched (Blackbox Tests), so this check is vacuous
+   except internally — covered by Phase 6.
+5. **Cross-cutting concerns**: haversine math (b81) is local. The
+   project does not yet have a shared geo-math module; if a second
+   consumer appears (e.g., spoof-distance check in FT-N-04), promote
+   to `runner/helpers/geo_math.py`. Tracked here, not flagged. ✓
+
+## Findings
+
+(None new at cumulative scope.)
+
+The two Low/Note findings from `batch_81_review.md`
+(`HintAckReport.passes` empty-hints semantic; FDR record loop branch
+ordering) remain as documented; both are scoped to b81 alone and
+neither is exacerbated by viewing b79/b80/b81 jointly. Carry over
+to the next cumulative cycle if a future batch touches the same
+files.
+
+## Regression Gate (cumulative)
+
+Full `e2e/_unit_tests/` suite: **746 passing in 147.57 s**.
+
+Baseline history across the arc:
+
+| Cumulative window | Suite count | Δ |
+|-------------------|-------------|---|
+| Pre-batch-79      | ~625        |   |
+| Post-batch-79     | 686         | +61 (FT-P-02 builder scenario tests) |
+| Post-batch-80     | 700         | +14 (strategy reorganisation; finer-grained per-strategy tests) |
+| Post-batch-81     | 746         | +46 (FT-P-12/13 unit + scenario fixtures) |
+
+No tests removed without an equivalent replacement
+(`test_common_module_exports_used_by_b01` retired in b80 because
+the "shared helper" pattern it pinned is now structural rather than
+file-location-based). No flakes observed across the three full-suite
+runs that closed each batch.

_docs/_autodev_state.md

@@ -6,15 +6,15 @@ step: 10
 name: Implement Tests
 status: in_progress
 sub_step:
-  phase: 11
+  phase: 0
-  name: commit-batch
+  name: awaiting-invocation
-  detail: "batch 81"
+  detail: ""
 retry_count: 0
 cycle: 1
 tracker: jira
-last_completed_batch: 80
+last_completed_batch: 81
-last_cumulative_review: batches_76-78
+last_cumulative_review: batches_79-81
-current_batch: 81
+current_batch: 82
 
 last_step_outcomes:
   step_8: "Code is testable — no changes needed (testability_assessment.md committed; no list-of-changes, no source edits)"