config/default.py holds defaults using ~/lib/data/tfl (expanduser, so safe
to commit). app.py loads it then overlays config/local.py if present, pushing
paths into cache and circle_line modules. config/local.py is gitignored for
machine-specific absolute paths (e.g. on the server where www-data runs).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Cache reads now accept an optional ttl (seconds). get_cached checks the
file mtime and returns None if the entry is older than the TTL, triggering
a fresh fetch. Eurostar prices use a 24-hour TTL; timetable caches remain
indefinite (date-scoped keys become irrelevant once the date passes).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
