Add normalized (ASCII-only) fields to Typesense schema and indexer so
users can search without diacritics (e.g. "can ho" finds "căn hộ").
Create synonym collection for HCMC district abbreviations and common
property-type aliases. Enable num_typos:2 for fuzzy matching.
- Add 7 normalized fields (title, description, address, ward, district,
city, projectName) using Address.normalize() at index time
- Search queries both original Vietnamese and normalized field sets
- Upsert 28 Vietnamese synonym rules on collection init
- Normalize user query to ASCII alongside original for dual matching
- Update tests for new fields and synonym upsert behavior
Co-Authored-By: Paperclip <noreply@paperclip.ing>