The stored ua_pretty froze each record at the uarite version of its
record time (old records showed disguised Meta crawlers as
"Chrome/145 Windows"). Client now carries a display-time-only
"uarite" field holding the full uarite.UA dataclass (pretty/engine/
os/provider/kind/url), filled when the viewer payload is built, so old
data always follows the current uarite. uarite 0.2.0 fixes the Meta
misdetection itself; _compact_user_agent is gone, tracking.py calls
uaparse directly.