feat(pg2pulsar): add Tables option to filter published tables

[KennyChenFight]

Summary

Add support for specifying tables to capture in pg2pulsar. When Tables is empty (default), all tables are captured. When specified, only the listed tables are included in the PostgreSQL publication.

• Add Tables field to PGXSource struct
• Add --Tables flag to pg2pulsar and configure commands
• Use pgx.Identifier for safe SQL identifier quoting (prevents SQL injection)
• Default to public schema when table name has no schema prefix
• Auto-include pgcapture.ddl_logs for DDL replication support

Note: This feature only works with the pgoutput decode plugin.

Known Limitations

⚠️ DDL events include all tables: When using --Tables to filter specific tables, pgcapture.ddl_logs is automatically included to support DDL replication. However, ddl_logs captures DDL changes for all tables in the database (via PostgreSQL event triggers), not just the specified tables.

This means:

• The downstream sink will receive DDL events for tables not in the --Tables list
• If the downstream PostgreSQL only has the filtered tables, DDL operations on other tables may fail (e.g., ALTER TABLE other_table will error with "relation does not exist")

Possible future improvements:

• Filter DDL events at the source or sink level by parsing the DDL query
• Add an --IncludeDDL flag to let users opt-out of DDL replication

Changed Files

• pkg/source/postgres.go - Core implementation
• pkg/sql/source.go - SQL template for table-specific publication
• cmd/pg2pulsar.go - CLI flag
• cmd/configure.go - Agent config flag
• cmd/agent.go - Parameter handling

[KennyChenFight]

We might need to include the pgcature.ddl_logs for being able to capture the DDL commands.

fixed in https://github.com/replicase/pgcapture/pull/83/commits/8e189e3ddd56b287faaa56cb1154849cc28d12e0