v0.7.0

Changes

• Fix nullable params: Cross-reference table catalog to restore column nullability for parameters. sqlc marks params as not_null because a value is provided, but the target column may be nullable. Now generates Option(Type) + pg.nullable() for params targeting nullable columns.
• Recover INSERT param names: For cast params like $5::uuid where sqlc strips the column name, parse the INSERT column list to recover the target column name. Enables both proper naming (project_id vs param_5) and nullability restoration.