rosreestr_deals open dataset contains both ДКП (resale, ~110-120K ₽/м²) and
ДДУ (developer pre-sale, ~177-200K ₽/м²). Mixed import previously skewed
secondary-market median, forcing PR #504 to disable deals output entirely.
This PR fixes the root cause: filter doc_type='ДКП' in import-rosreestr.sh
(WHERE clause) and re-enable _fetch_deals() call in estimator.py (was stubbed
to deals=[] since PR #504). dedup_hash prefix changed to 'ros:dkp:' to allow
future ДДУ import as separate source without collision.
Also fix pre-existing broken mock in test_estimator_cian_integration.py:
_fetch_analogs returns 3-tuple (list, bool, str) but mocks passed ([], False)
— updated to ([], False, 'W') matching actual signature.
Post-merge ops (NOT in this PR):
DELETE FROM deals WHERE source='rosreestr' AND dedup_hash NOT LIKE 'ros:dkp:%';
./deploy/import-rosreestr.sh # на prod
Tests: _fetch_deals already mocked in test_estimator_cian_integration.py.
Refs: Decision_TradeIn_DataQuality_8PR_Roadmap (PR #504 reversed properly).
