id: CORE-001D2C
title: Price Feed Cache and Provider Normalization Boundary
status: done
priority: P2
effort: S
depends_on:
  - CORE-001D2A
tags:
  - core
  - decimal
  - cache
  - provider
summary: PriceFeed now uses explicit cache/provider payload normalization instead of ad-hoc raw dict handling.
completed_notes:
  - Added explicit cached/provider payload normalization in `app/services/price_feed.py`.
  - Removed the stale direct cache API usage and aligned `PriceFeed` with `CacheService.get_json(...)` / `set_json(...)`.
  - Cached symbol mismatches and malformed cached payloads are discarded instead of being trusted.
  - Added focused regression coverage in `tests/test_price_feed.py` for cache hits, malformed cache fallback, invalid provider payload rejection, and normalized cache writes.
  - Validated with focused pytest coverage and `make build` on local Docker.