## Summary
- Adds a `BankFormatter` interface with a `BbvaFormatter` implementation
that transforms ALL CAPS `//`-separated BBVA descriptions into readable
Title Case (preserving acronyms like SEPA, S.A., BIZUM and Spanish
stopwords)
- Stores the raw description in a new `original_description` column when
formatting changes it, keeping sync matching intact
- Existing non-BBVA banks and null-bank transactions pass through
unchanged
## Test plan
- [x] Unit tests for `BbvaFormatter` (11 tests: title case, acronyms,
stopwords, reference numbers, mixed-case passthrough, whitespace)
- [x] Unit tests for `TransactionDescriptionFormatter` dispatcher (4
tests: BBVA match, no-match, null bank)
- [x] Feature tests for BBVA sync integration (formatted description +
original stored)
- [x] Feature tests for non-BBVA sync (description unchanged, original
null)
- [x] All 25 existing + new tests pass
- [x] Pint formatting clean
9242b3fe5f