[Feature Request]: managed IO connector for Apache Iceberg to offer Configurable Write Options for Target Table

[eder001]

What would you like to happen?

Current Limitation: The managed IO connector for Apache Iceberg currently only supports appending data to tables, limiting users to a single write option.
Requirement: Introduce additional write options—specifically overwrite, append, and update—for Dataflow’s Iceberg connector, mirroring the write modes Spark offers for Iceberg integration.

Issue Priority

Priority: 2 (default / most feature requests should be filed as P2)

Issue Components

• Component: Python SDK
• Component: Java SDK
• Component: Go SDK
• Component: Typescript SDK
• Component: IO connector
• Component: Beam YAML
• Component: Beam examples
• Component: Beam playground
• Component: Beam katas
• Component: Website
• Component: Infrastructure
• Component: Spark Runner
• Component: Flink Runner
• Component: Samza Runner
• Component: Twister2 Runner
• Component: Hazelcast Jet Runner
• Component: Google Cloud Dataflow Runner