fix(jdbc-v2): render array contents for named tuples

[014-code]

Summary

• Make JDBC Array values display their nested contents.
• Support readable rendering of Array(Tuple(...)) values with named tuple elements.
• Preserve the existing java.sql.Array return type and getArray() behavior.
• Add unit and integration regression tests.
• Update CHANGELOG.md.

Problem

When JDBC v2 returned an array containing a named tuple, clients such as IntelliJ IDEA could display the value as:

com.clickhouse.jdbc.types.Array@54c3b772

For example:

SELECT [('550e8400-e29b-41d4-a716-446655440000')::Tuple(id UUID)];

The actual contents were available through java.sql.Array#getArray(), but the JDBC wrapper inherited Object#toString(), which produced an unreadable class name and identity hash.

Fixes #3045.

Changes

com.clickhouse.jdbc.types.Array#toString() now uses deep array formatting via Arrays.deepToString(...).

The value is now rendered as:

[[550e8400-e29b-41d4-a716-446655440000]]

Nested arrays and tuple values are also rendered correctly.

Compatibility

No public API signatures, JDBC return types, or array contents were changed.

This change only improves the textual representation returned by com.clickhouse.jdbc.types.Array#toString().

Tests

Added:

• ArrayTest#testToStringForArrayOfNamedTuples

  • Verifies deep formatting of Array(Tuple(id UUID)).
  • Passed: 1 test, 0 failures.

• ArrayTupleIntegrationTest#testArrayOfNamedAndUnnamedTuplesToString

  • Runs against ClickHouse using Docker.
  • Covers both named and unnamed tuple arrays.
  • Verifies ResultSet#getObject() returns java.sql.Array.
  • Verifies toString() matches the contents returned by Array#getArray().
  • Passed: 1 test, 0 failures.