[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/02_tasks/done/AZ-420_ft_p_12_13_gcs.md

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+# FT-P-12 + FT-P-13 — GCS downsample + GCS command path
+
+**Task**: AZ-420_ft_p_12_13_gcs
+**Name**: GCS 1-2 Hz downsample + GCS-originated re-loc hint (AC-6.1, AC-6.2)
+**Description**: Implement FT-P-12 (position estimates + confidence stream to GCS via `mavproxy-listener` at 1-2 Hz) and FT-P-13 (GCS-originated `STATUSTEXT` carrying operator re-loc hint biases the next anchor attempt). Both share the mavproxy listener fixture.
+**Complexity**: 3 points
+**Dependencies**: AZ-406, AZ-407
+**Component**: Blackbox Tests / Positive / GCS / Telemetry (epic AZ-262)
+**Tracker**: AZ-420
+**Epic**: AZ-262 (E-BBT)
+
+## Problem
+
+The GCS leg is the operator's only window into the SUT during flight; the downsample rate must be measured (operator UX) AND the command path must be validated (operator override is a real safety mechanism per AC-6.2).
+
+## Outcome
+
+- pytest scenario at `e2e/tests/positive/test_ft_p_12_gcs_downsample.py` (FT-P-12) and `test_ft_p_13_gcs_command.py` (FT-P-13).
+- FT-P-12: 60 s Derkachi replay; mavproxy listener captures `.tlog`; parse for SUT-emitted GCS messages; assert observed rate ∈ [1, 2] Hz inclusive.
+- FT-P-13: SUT in `dead_reckoned` state (e.g. mid-blackout from FT-N-03 setup); send re-loc-hint STATUSTEXT from mavproxy; SUT acknowledges via FDR log entry; next anchor attempt uses the hint as a search prior.
+
+## Scope
+
+### Included
+- mavproxy listener `.tlog` capture (already provided by AZ-406).
+- SUT-emitted GCS message rate computation over the 60 s window.
+- Re-loc-hint STATUSTEXT injection (FT-P-13).
+- FDR-side acknowledgement detection.
+- Boolean assertion that the post-hint anchor attempt biases its search.
+
+### Excluded
+- Spoofed GPS escalation STATUSTEXT — owned by FT-N-04 (AZ-426).
+- Operator-reloc-request emission (negative-path) — owned by FT-N-03 (AZ-425).
+
+## Acceptance Criteria
+
+**AC-1: FT-P-12 — GCS rate**
+Given a 60 s Derkachi replay
+When the test parses the captured `.tlog` for SUT-emitted GCS messages
+Then the observed rate over the 60 s window is in `[1, 2]` Hz inclusive.
+
+**AC-2: FT-P-13 — hint acknowledgement**
+Given the SUT is in `dead_reckoned` state
+When the test injects a re-loc-hint STATUSTEXT from mavproxy
+Then the FDR contains a log entry referencing the hint within ≤2 s of the inject.
+
+**AC-3: FT-P-13 — search prior bias**
+Given the next nav-camera frame is pushed after the hint
+Then the next satellite-anchor attempt observably uses the hint as a search prior. Observable signal: the FDR's per-frame "anchor-search-region" record (AC-NEW-3 schema) shifts toward the hinted location.
+
+**AC-4: FT-P-13 — no rejection**
+Given the hint is well-formed
+Then the SUT does NOT reject the hint with a security/auth error (this is a positive-path scenario; security rejection is out of scope here).
+
+**AC-5: parameterization**
+Given conftest parameterization
+Then both methods run per `(fc_adapter, vio_strategy)`.
+
+## System Under Test Boundary
+
+End-to-end through public boundaries.
+
+- **Allowed**: mavproxy listener (`.tlog` capture), STATUSTEXT injection (via mavproxy command), FDR archive read.
+- **Forbidden**: querying SUT internal anchor-search state; the bias signal must be readable from FDR (or the AC isn't meaningfully validated).
+
+## Constraints
+
+- "Anchor-search-region" record is part of the AC-NEW-3 FDR schema; if absent, the test fails for AC-3 (cannot validate the bias without observable evidence).
+
+## Document Dependencies
+
+- `_docs/02_document/tests/blackbox-tests.md` § FT-P-12, § FT-P-13
+- `_docs/02_document/tests/test-data.md` § Resilience / GCS