[AZ-343] C2.5 InlierCountReRanker + shared FeatureExtractor helper

Implements the production-default ReRankStrategy: K=10 → N=3 by
single-pair LightGlue inlier count, with strict drop-and-continue
(INV-8) on per-candidate TileFetch / backbone / zero-inlier failures
and RerankAllCandidatesFailedError on zero survivors. Composition
root injects the shared LightGlueRuntime + Clock + the new
FeatureExtractor helper (an L1 placeholder OpenCvOrbExtractor that
unblocks AZ-343 and future C3 strategies — task scope expansion).

Architectural notes:
- Cross-component imports stay banned; tile_store types as `object`
  and the C6 TileCacheError family is duck-typed by class module
  prefix (same workaround AZ-348 adopted for c7_inference; proper
  fix is to relocate TileCacheError to _types/ in a follow-up).
- Clock injection follows the replay contract (AZ-398 Invariant 2);
  reranked_at is sourced from clock.monotonic_ns().
- AZ-342 factory grew `feature_extractor` + `clock` + `fdr_client`
  parameters; existing AZ-342 conformance tests updated.

Tests: 19 new AC-1..AC-12 + mixed-failure scenarios in
test_inlier_count_reranker.py; existing AZ-342 suite (26) still
green. Full repo sweep 1093 passed / 2 skipped (cmake/actionlint
not on PATH).

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

_docs/_autodev_state.md

@@ -8,7 +8,7 @@ status: in_progress
 sub_step:
   phase: 2
   name: detect-progress
-  detail: "batch 24 complete (AZ-336, AZ-342, AZ-344, AZ-348 per-task commits); ready to plan batch 25"
+  detail: "batch 25 in progress: AZ-343 implemented (InlierCountReRanker + shared FeatureExtractor helper, 19 AZ-343 tests + 26 AZ-342 tests green, full sweep 1093 passed/2 skipped); pending AZ-345, AZ-332"
 retry_count: 0
 cycle: 1
 tracker: jira