[improve][test] JDBC SQLite sink: optionally align embedded test with shared JDBC harness

## Current state (correction)

`jdbc/sqlite` **already has integration coverage**: `SqliteJdbcSinkTest` / `SqliteJdbcSinkBatchTest` run `SqliteJdbcAutoSchemaSink` end-to-end against a real embedded SQLite database (in-process `jdbc:sqlite:` via `SqliteUtils`), covering insert/update/batch paths. This is genuine functional coverage — an earlier triage note incorrectly listed this as a gap.

## Enhancement (optional, not a gap)

Optionally fold the SQLite variant into the shared JDBC integration approach used by the clickhouse/mariadb/postgres modules so all JDBC sinks are exercised through one consistent harness. Embedded SQLite is a perfectly valid backend, so this is low priority and may reasonably be declined.

This is a test-consistency improvement, not a coverage gap.

Start with SqliteJdbcSinkTest, SqliteJdbcSinkBatchTest, SqliteJdbcAutoSchemaSink, and SqliteUtils, then compare the shared JDBC integration approach used by the clickhouse, mariadb, and postgres modules. Done means the SQLite variant is optionally exercised through the same consistent harness while retaining its existing embedded integration coverage.

Written by the indexing model from the issue text.