ROW_NUMBER() was partitioning by `group`, collapsing all 12 US/* timezones
(which share group="United States") down to a single record. Partitioning
by `name` correctly deduplicates by timezone identity while still preserving
the object > account > global override hierarchy.
Priority-only list now returns the expected 72 entries. Adds a regression
test asserting all 12 US/* timezones are present in the full list.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
