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Description

Description

Motivation

This is a subtask of #4608.

After the consumer-offset table foundation, RPC contract, and owner discovery are in place, the server needs to return committed consumer offsets so clients can resume from committed positions.

Scope

• Implement GET_CONSUMER_OFFSETS on TabletServer.
• Decode all-offset and selected-bucket requests and build table-grouped responses.
• Read committed offsets from the local leader replica.
• Reorder the consumer-offset primary key to record_type, group_id, table_id, partition_id, bucket_id.
• Scan committed offsets by the record_type + group_id prefix.
• Decode values through the schema getter so old and new value schemas can be read together.
• Require DESCRIBE permission on every source table named in a selected-bucket request.
• Add unit, RPC, and integration tests for all-offset and selected-bucket reads, mixed schema versions, authorization, and partitioned/non-partitioned tables.
• Update the authorization documentation.

Out of scope

• Consumer-group ACL resource and group-level DESCRIBE enforcement
• Client-side consumer-offset APIs and owner caching
• Consumer-group listing and deletion

Willingness to contribute

• I'm willing to submit a PR!