Step 8: Code Testability Revision — no changes needed

Autodev greenfield Step 8 closes with outcome
"Code is testable — no changes needed" after reviewing the 41 test
scenarios in _docs/02_document/tests/ against the codebase against the
Step-8 allowed-changes checklist.

Key findings:
- Hardcoded paths are config defaults, overridable via Config dataclass
- All mutable registries expose clear_*_registry()/_reset_for_tests()
- Hot-path timing uses injected Clock; cosmetic timestamps are
  monkeypatch-safe (2105-test unit suite proves it)
- Heavy strategies (OKVIS2, VINS-Mono, FAISS, TRT) are BUILD_* gated
- compose_root(pre_constructed=...) (AZ-591) is the Tier-1 injection
  seam; tests/e2e/replay already drives it end-to-end

Artifacts:
- _docs/04_refactoring/01-testability-refactoring/
  testability_assessment.md
- State advanced to Step 9 (Decompose Tests)
- last_step_outcomes.step_8 recorded

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

_docs/_autodev_state.md

@@ -2,8 +2,8 @@
 
 ## Current Step
 flow: greenfield
-step: 8
-name: Code Testability Revision
+step: 9
+name: Decompose Tests
 status: not_started
 sub_step:
   phase: 0
@@ -16,3 +16,5 @@ last_completed_batch: 66
 last_cumulative_review: batches_61-63
 current_batch: 67
 current_batch_tasks: ""
+last_step_outcomes:
+  step_8: "Code is testable — no changes needed (testability_assessment.md committed; no list-of-changes, no source edits)"