refactor(postgres): inject logger dependency into client

Modifies the HtDataPostgresClient to accept a Logger instance via its constructor instead of creating one internally.

This change improves testability by allowing mock loggers to be injected and follows the Dependency Inversion Principle, giving the consumer full control over logger configuration and hierarchy.

Author: fulleni

lib/src/ht_data_postgres.dart

@@ -18,9 +18,11 @@ class HtDataPostgresClient<T> implements HtDataClient<T> {
     required this.tableName,
     required this.fromJson,
     required this.toJson,
-  }) : _queryBuilder = _QueryBuilder(tableName: tableName);
+    required Logger log,
+  })  : _queryBuilder = _QueryBuilder(tableName: tableName),
+        _log = log;
 
-  final _log = Logger('HtDataPostgresClient<$T>');
+  final Logger _log;
 
   /// The active PostgreSQL database connection.
   final Connection connection;