refactor(*): Implement CSV-based seeding, dynamic box placement, and enforce forms from pokedex configuration

supabase/migrations/20260104000002_create_regional_dex_numbers.sql

@@ -0,0 +1,21 @@
+-- Create regional_dex_numbers table for generic regional dex number storage
+-- This table replaces region-specific columns (kanto_dex_number, johto_dex_number, etc.)
+-- and allows adding new regions without schema changes
+
+CREATE TABLE IF NOT EXISTS regional_dex_numbers (
+  id SERIAL PRIMARY KEY,
+  pokedex_entry_id INT NOT NULL REFERENCES pokedex_entries(id) ON DELETE CASCADE,
+  region TEXT NOT NULL,
+  dex_number INT NOT NULL,
+  UNIQUE(pokedex_entry_id, region)
+);
+
+-- Create indexes for better query performance
+CREATE INDEX IF NOT EXISTS idx_regional_dex_numbers_region ON regional_dex_numbers(region, dex_number);
+CREATE INDEX IF NOT EXISTS idx_regional_dex_numbers_entry ON regional_dex_numbers(pokedex_entry_id);
+
+-- RLS policies (read-only reference data, same pattern as pokedex_entries)
+ALTER TABLE regional_dex_numbers ENABLE ROW LEVEL SECURITY;
+
+CREATE POLICY "Allow public read access" ON regional_dex_numbers
+  FOR SELECT USING (true);