Add `data-diff` Support for Clickhouse

[terzioglub]

Clickhouse is missing GetTableSummary method implementation, preventing it from using the bruin data-diff command. Currently only postgres, bigquery, snowflake, and duckdb support data-diff.

The GetTableSummary method analyzes a table's schema and data statistics to enable comparison between tables. It returns column information (types, constraints) and statistical data (row counts, null counts, min/max values, averages) that bruin data-diff uses to identify differences between tables.

More about data-diff on : https://getbruin.com/docs/bruin/commands/data-diff.html

Implementation

Add GetTableSummary method for the database . The implementation of getTableSummary already exists for bigquery , duckdb , snowflake and Postgres . Take a look at the functions in their packages db.go clickhouse should support the same functionality.

func (db *DB) GetTableSummary(ctx context.Context, tableName string, schemaOnly bool) (*diff.TableSummaryResult, error) {
    // Follow pattern from pkg/postgres/db.go or pkg/duckdb/db.go
    // Return table statistics for data comparison
}

Acceptance Criteria

• GetTableSummary method implemented in pkg/clickhouse/db.go
• bruin data-diff works for blockhouse
• Schema comparison works (column types, nullable, constraints)
• Data comparison works (row counts, column statistics)
• --schema-only flag works
• Test cases