fix(ascii): replace all non-ASCII chars in Python source files

fix(BUG-C4): add scraped_at field to all seed records so live feed shows data after /admin/seed

fix(seed): DIRECTOR_LINKS keys politician_name→name_a — was creating zero relationships

fix(seed): add DIRECTOR_OF + WON_CONTRACT relationships to sample data

fix(data): schema session bug and seed data field mismatches

fix(data): add sample data seed — politicians, companies, contracts, audit reports