• Requires basalt >=0.1.0 <0.2.0 — the new table-marker shape (final class X extends TableRef<X> with owner-linked columns).
• Raised the driver lower bound to postgres ^3.5.0 — the connection uses TxSession, which older 3.x versions don't ship (fixes downgrade analysis).
• No functional changes.

• PostgresDialect.castType — implements the new SqlDialect seam, mapping the core types to native Postgres names (IntSqlType → bigint, DateTimeSqlType → timestamptz, ...) so the VALUES table of a batch updateAll stays preparable; unwraps NullableSqlType.
• PostgresTypedSqlType — new opt-in interface for custom codecs to name their native type; implemented by PostgresJsonbSqlType (jsonb), PostgresUuidSqlType (uuid), PostgresNumericSqlType (numeric) and PostgresArraySqlType (common element types).
• Requires basalt >=0.0.2 <0.1.0.

Initial development release of the Postgres backend for basalt_dart.

• PostgresDialect — the SqlDialect implementation with $N placeholders and quoted identifiers.
• PostgresConnection — an async Connection over package:postgres with transactions and nested SAVEPOINT support.
• information_schema introspection (tables, columns, nullability, primary & foreign keys; arrays keyed by udt_name) for the CLI's generate-schema.
• PostgresAdapter / PostgresEndpoint (lib/adapter.dart) — the BasaltAdapter CLI seam.
• Native PG type codecs, emitted by the adapter's native_types preset: PostgresJsonbSqlType (json/jsonb), PostgresUuidSqlType (uuid), PostgresNumericSqlType (exact decimal as String), and PostgresArraySqlType<E> (integer[]/text[]/double[]/boolean[], …).