feat: default generate to use pglite so postgres is not required (@algora-pbc /claim #2) - #51

Description

@algora-pbc /claim #2

Closes #2

Summary of Changes

1. Default PGlite in generate(): Changed pglite default parameter to true in src/generate.ts so type generation works out-of-the-box without requiring a running Postgres instance.
2. CLI Configuration: Updated src/cli.ts to default --pglite to true while allowing explicit --no-pglite opt-out for external database connections.
3. Project Scaffolding: Updated src/init.ts so newly scaffolded projects configure db:generate with pgstrap generate --pglite.