fix(lookup): partition dedup by name instead of group

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>

app/methods/lookup_methods.py

@@ -28,8 +28,8 @@ def get_lookup_list_v3(
         SELECT * FROM (
             SELECT *, 
                    ROW_NUMBER() OVER (
-                       PARTITION BY `group`
-                       ORDER BY 
+                       PARTITION BY `name`
+                       ORDER BY
                           (for_type = :for_type AND for_id = :for_id) DESC,
                           (account_id = :account_id) DESC, 
                           created_on DESC