Switch library hierarchy to GW webshop taxonomy

- warhammer_data.py: GW naming throughout - Space Marine chapters are
  their own factions under a 'Space Marines' group, systems match the
  shop (Age of Sigmar, The Horus Heresy, Other Games, The Old World,
  Middle-Earth), classes are GW shop categories (Battleline, Infantry,
  Vehicle, Walker, Flyer, Monster, Mounted, Hero, Titanic), group map
  extended to AoS grand alliances / Other Games / Old World / Middle-Earth
- gwshop.py: hierarchy remap - GW depth-4 paths are system/group/faction/
  class (the shop's last level is the class layer), depth-5 sources keep
  a subfaction before it; catalog snapshot regenerated accordingly
- sorter.py: catalog entry is hierarchy-authoritative (group, class, and
  faction when GW moved a unit or keyword tables are stale); generic GW
  branches ('Unit Type') and a Battleline default never degrade a
  confident keyword classification; whole-catalog retry when the faction
  pool has no confident match (handles units GW moved between factions);
  whole-catalog matching also runs when keyword classification found no
  faction; invalid (HTML) items never fuzzy-match; default catalog is
  now data/gwshop_catalog.json
- catalogue.py: --apply moves include the group layer, same structure
  as the sorter
- docs/SORTING.md: hierarchy rewritten to GW naming with examples
- tests: expectations updated to GW naming (chapters, unit types)
- verified live: 4/4 real files in the test batch now catalog-match,
  e.g. The Twin Lance -> 40k/Xenos Armies/T'au Empire/Epic Hero (GW's
  current placement) instead of the stale Drukhari keyword

dlphelper/gwshop.py

@@ -257,15 +257,24 @@ def build_catalog(hits: list[dict]) -> dict:
             )
             continue
         # primary branch = longest path (most specific), e.g.
-        # [40k, Armies of the Imperium, Adeptus Custodes, Rules & Accessories]
+        # [40k, Space Marines, Raven Guard, Walker]
         primary = max(paths, key=len)
         system = primary[0] if len(primary) > 0 else None
         group = primary[1] if len(primary) > 1 else None
         faction = primary[2] if len(primary) > 2 else None
-        subfaction = primary[3] if len(primary) > 3 else None
-        # 5th level (if present) is treated as class; GW uses "Rules &
-        # Accessories" etc. rather than force-org classes.
-        klass = primary[4] if len(primary) > 4 else None
+        # The LAST level is the class/category layer (GW uses shop
+        # categories there: Battleline, Walker, Vehicle, "Rules &
+        # Accessories", product lines like "Cadian"). Deeper sources
+        # (miniset style) may carry a real subfaction before it.
+        if len(primary) >= 5:
+            subfaction = primary[3]
+            klass = primary[4]
+        elif len(primary) == 4:
+            subfaction = None
+            klass = primary[3]
+        else:
+            subfaction = None
+            klass = None
         key = (hit.get("objectID"), tuple(primary))
         if key in seen:
             continue