[feat][io] Add Debezium CockroachDB source connector

[david-streamlio]

Motivation

Debezium ships a CockroachDB source connector (io.debezium:debezium-connector-cockroachdb, present in the debezium-bom at our pinned version), but this repository does not wrap it. We currently wrap 5 of Debezium's 12 source connectors: MySQL, PostgreSQL, MongoDB, Oracle, and SQL Server.

Unlike the other gaps, this connector does not use the logical-decoding or binlog machinery — it consumes CockroachDB's native changefeeds.

Proposal

Add a debezium/cockroachdb module (pulsar-io-debezium-cockroachdb) following the structure of the existing Debezium modules:

• DebeziumCockroachDbSource extending DebeziumSource
• include("debezium:pulsar-io-debezium-cockroachdb") in settings.gradle.kts
• debezium-connector-cockroachdb = { module = "io.debezium:debezium-connector-cockroachdb" } in the version catalog
• NAR packaging + distribution wiring
• A Testcontainers integration test using the cockroachdb/cockroach image (start-single-node --insecure), enabling rangefeeds (SET CLUSTER SETTING kv.rangefeed.enabled = true) and creating a changefeed in setup

Notes

• This is the newest and least battle-tested connector of the set — it arrived in the 3.4 line. Treat it as lower priority than [feat][io] Add Debezium MariaDB source connector #65 (MariaDB) and Db2 unless there is concrete user demand, and expect the connector's own behavior to shift across Debezium minors (see the migration tracked in [improve][io] Migrate Debezium from the 3.4.x line to 3.6.0.Final #63).
• Because it uses native changefeeds rather than the standard relational CDC path, verify the emitted record shape and offset semantics match what DebeziumSource and PulsarSchemaHistory expect — it may not need schema history at all.
• Use the GenericContainer pattern (see the Testcontainers version conflict noted in [improve][test] Add Debezium Oracle source integration test #62).

Identified by a scan of the Debezium connector catalog against our connector inventory.