[Phase 0] Introduce canonical mapping tables for MVP entities #337
Description
Type: feature
Suggested labels: phase-0, dbt, canonical-model
Add mapping logic/tables to reconcile source-native IDs into canonical IDs for competitions, clubs, and matches.
Acceptance criteria:
- New mapping tables exist (for example map_competition_ids, map_club_ids, map_match_ids).
- Mapping includes confidence score and resolution method.
- Ambiguous mappings are flagged and excluded from curated outputs until resolved.
Dependencies: #5