test: add 25-test suite + fix sum_nutriments display keys
- 25 integration tests: DB init, default goals, FTS5 cache, upsert,
portion scaling (100g/50g/200g/empty/non-numeric), sum_nutriments
(single/multiple/empty/partial/no-data), meal detection, date format,
log entry + summary round trip, custom food + sum, delete entry,
goals get/update, weight log + history + upsert
- Fix: sum_nutriments now uses TRACKED_NUTRIENTS display names (first
tuple element) instead of deriving from OFF field names — fixes
proteins→protein, energy-kcal→energy_kcal mismatches
- Fix: weight_log.date is now UNIQUE for proper upsert behavior
- Fix: build_daily_summary remaining keys use display names
- Added lib.rs for integration test access
- Added regex dev-dependency
Closes nutrition-mcp-45t
Anthony Merlo
ebb44fd712