Normalise route naming scheme to 'Route X (Region)' format

Standardise 426 inconsistent route names across 33 seed data files
(game data + boss files). Converts 'Region Route X' prefix style and
'Route X - Region' dash style to the consistent 'Route X (Region)' format.

Resolves beans-r48e.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/src/app/seeds/data/platinum.json

@@ -731,7 +731,7 @@
     ]
   },
   {
-    "name": "Sinnoh Route 204",
+    "name": "Route 204 (Sinnoh)",
     "order": 12,
     "encounters": [],
     "children": [
@@ -1100,7 +1100,7 @@
     ]
   },
   {
-    "name": "Sinnoh Route 205",
+    "name": "Route 205 (Sinnoh)",
     "order": 16,
     "encounters": [],
     "children": [
@@ -3949,7 +3949,7 @@
     ]
   },
   {
-    "name": "Sinnoh Route 210",
+    "name": "Route 210 (Sinnoh)",
     "order": 63,
     "encounters": [],
     "children": [
@@ -5326,7 +5326,7 @@
     ]
   },
   {
-    "name": "Sinnoh Route 212",
+    "name": "Route 212 (Sinnoh)",
     "order": 80,
     "encounters": [],
     "children": [
@@ -6836,7 +6836,7 @@
     ]
   },
   {
-    "name": "Sinnoh Route 211",
+    "name": "Route 211 (Sinnoh)",
     "order": 98,
     "encounters": [],
     "children": [
@@ -8356,7 +8356,7 @@
     ]
   },
   {
-    "name": "Pok\u00e9mon League (Sinnoh)",
+    "name": "Pokémon League (Sinnoh)",
     "order": 119,
     "encounters": [
       {