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>
Foundational scaffolding for the InlierCountReRanker (AZ-343) and
the future C3 CrossDomainMatcher consumer (AZ-344). No concrete
re-ranker is implemented here.
* ReRankStrategy Protocol (single rerank(frame, vpr_result, n,
calibration) -> RerankResult method) with all 8 invariants in the
docstring — notably INV-8 drop-and-continue (per-candidate failure
NEVER propagates unless every candidate fails).
* DTOs moved to L1 _types/rerank.py — RerankCandidate, RerankResult;
frozen+slots; tuple-not-list for RerankResult.candidates; tile_id
encoded as (zoom_level, lat, lon) tuple to keep _types/ free of any
c6_tile_cache (L3) import per module-layout.md.
* Error family: RerankError + RerankBackboneError +
RerankAllCandidatesFailedError. Only RerankAllCandidatesFailedError
escapes rerank(); RerankBackboneError is caught inside the per-
candidate loop, logged ERROR, FDR-stamped, candidate dropped.
* C2_5RerankConfig (strategy enum default "inlier_count", top_n int
default 3) with strict validation at load; registered into
Config.components on c2_5_rerank import.
* build_rerank_strategy(config, *, tile_store, lightglue_runtime)
factory: 1-strategy resolution table, lazy import,
BUILD_RERANK_<variant> gate, ImportError → StrategyNotAvailableError
mapping. The shared LightGlueRuntime is constructor-injected
(R14 fix: neither C2.5 nor C3 owns its lifecycle).
Renamed the Protocol from the existing stub "RerankStrategy" to
"ReRankStrategy" to match the contract; updated module-layout.md.
Removed the legacy RerankResult shape from _types/vpr.py — the
v1.0.0 shape lives in _types/rerank.py.
Excluded per task spec:
* Concrete InlierCountReRanker (AZ-343).
* C3 matcher protocol task (AZ-344, next in batch).
* AC-9 single-thread binding + AC-10 LightGlueRuntime identity-share
between C2.5/C3 — deferred per task spec Risk 3 until the generic
compose_root thread-binding registry and the C3 factory both land.
Tests: AC-1..AC-8 + AC-11 + NFR-perf-factory in
tests/unit/c2_5_rerank/test_protocol_conformance.py. The legacy
smoke test is removed. Full sweep: 997 passed (one pre-existing
flake in test_az296_takeoff_abort, subprocess timing, unrelated to
this commit; passes in isolation).
Co-authored-by: Cursor <cursoragent@cursor.com>
Oleksandr Bezdieniezhnykh