Behavior-preserving structural refactor: the ~870-line deterministic pricing
block inside estimate_quality() is extracted into a new pure synchronous function
_price_from_inputs() returning a PricingResult dataclass.
Key design decisions:
- All async DB fetches (imv_eval, yandex_val, cian_val) hoisted to estimate_quality
BEFORE the call; passed as pre-fetched values / bool flags.
- DB-dependent helpers whose arguments are computed inside the block (_get_asking_sold_ratio,
_lookup_quarter_index, _lookup_quarter_indexes) injected as Callable parameters
(ratio_resolver, quarter_index_lookup, quarter_indexes_lookup).
- _fetch_house_imv_anchor called once in estimate_quality (was two separate conditional
calls inside the block); single result passed as imv_anchor dict.
- _fetch_dkp_corridor and _fetch_anchor_comps hoisted to estimate_quality with
identical guards.
All 2443 existing tests pass UNMODIFIED. 9 new hermetic unit tests added that
call _price_from_inputs directly with stub callables.
