feat(pokemon): store official data identity separate from display ID

Add data_id and data_identifier to pokemon schema
Use official data ID as internal route ID for non-event pokemon
Prevent applying fetched data with mismatched ID to existing pokemon

backend/db/schema.sql

@@ -712,6 +712,8 @@ CREATE TABLE IF NOT EXISTS pokemon_types (
 
 CREATE TABLE IF NOT EXISTS pokemon (
   id integer PRIMARY KEY,
+  data_id integer CHECK (data_id > 0),
+  data_identifier text NOT NULL DEFAULT '',
   display_id integer NOT NULL CHECK (display_id > 0),
   name text NOT NULL UNIQUE,
   is_event_item boolean NOT NULL DEFAULT false,
@@ -738,6 +740,10 @@ CREATE TABLE IF NOT EXISTS pokemon (
   updated_at timestamptz NOT NULL DEFAULT now()
 );
 
+ALTER TABLE pokemon
+  ADD COLUMN IF NOT EXISTS data_id integer CHECK (data_id > 0),
+  ADD COLUMN IF NOT EXISTS data_identifier text NOT NULL DEFAULT '';
+
 CREATE TABLE IF NOT EXISTS pokemon_pokemon_types (
   pokemon_id integer NOT NULL REFERENCES pokemon(id) ON DELETE CASCADE,
   type_id integer NOT NULL REFERENCES pokemon_types(id) ON DELETE CASCADE,