fix(#64): Address PR comments

supabase/migrations/20260110150001_populate_existing_pokedex_mappings.sql

@@ -0,0 +1,25 @@
+-- Populate pokedex_entries_mapping for existing pokedexes
+-- This is a one-time migration to backfill data for pokedexes created before the mapping table
+
+-- Insert mappings for all existing pokedexes
+-- Apply the same filtering logic that the application uses to determine expected entries
+INSERT INTO pokedex_entries_mapping ("pokedexId", "pokedexEntryId")
+SELECT
+  p.id AS "pokedexId",
+  pe.id AS "pokedexEntryId"
+FROM pokedexes p
+CROSS JOIN pokedex_entries pe
+WHERE
+  -- Form filter: if isFormDex is false, only include base forms
+  -- Base forms have form IS NULL, except Unown which has no base form (use 'A')
+  (p."isFormDex" = true OR (pe.form IS NULL OR (pe.pokemon = 'Unown' AND pe.form = 'A')))
+  -- Game scope filter: if gameScope is specified, filter by game
+  AND (p."gameScope" IS NULL OR pe."gamesToCatchIn" @> ARRAY[p."gameScope"]::TEXT[])
+  -- Region filter: if gameScope is specified, filter by region
+  AND (p."gameScope" IS NULL OR pe."regionToCatchIn" = (
+    SELECT region FROM region_game_mappings WHERE game = p."gameScope" LIMIT 1
+  ))
+ON CONFLICT ("pokedexId", "pokedexEntryId") DO NOTHING;
+
+-- Add comment to document this migration
+COMMENT ON TABLE pokedex_entries_mapping IS 'Junction table defining which pokedex_entries belong to each pokedex. Used for accurate stats calculation.';