Set up the GraphQL server and define the initial schema

[agnesas]

Set up the GraphQL server using Node.js and TypeScript. Define the initial schema, including Pokémon types and queries needed to retrieve data.

• Create the backend package and TypeScript configuration
  Separate backend dependencies and development scripts.

• Define the initial Pokémon schema and queries
  Add the Pokemon type and the two query definitions.

• Start the GraphQL server on port 3001
  Verify that the endpoint starts without errors.

• Execute test queries successfully
  Confirm that both queries execute against the schema.

• Document how to run the backend
  Add setup instructions to the appropriate README.