- Add towns table with town_pid, town_name, state, population, town_class, date_retired
- Add AustralianState enum with label and abbreviation helpers
- Add Town model with active() and search() scopes
- Add SyncTowns job that paginates ArcGIS API and upserts all 1977 towns
- Schedule SyncTowns to run nightly at 02:00
- Add /towns/search endpoint returning JSON suggestions filtered by name and state
- Add Alpine-powered autocomplete on origin/destination fields in create form
- Add state filter dropdown in journeys card header to narrow autocomplete results
