Revert "Revert "add bidirectional streaming support for external snapshot streaming""

[shivaji-kharse]

Reverts #274

[Copilot]

Pull Request Overview

This PR reverts a previous revert to restore bidirectional streaming support for external snapshot streaming. It changes the StreamExtSnapshot RPC from client-streaming to bidirectional streaming by enabling server streams and updating the associated client/server interfaces.

• Enables bidirectional streaming for StreamExtSnapshot RPC method
• Updates gRPC client and server interfaces to support sending/receiving in both directions
• Adds a finish field to StreamExtSnapshotResponse message

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
protos/api.v2.proto	Updates StreamExtSnapshot RPC definition to bidirectional streaming and adds finish field to response
protos/api.v2/api.v2.pb.go	Updates generated protobuf code with new StreamExtSnapshotResponse structure and finish field getter
protos/api.v2/api.v2_grpc.pb.go	Updates generated gRPC code with bidirectional streaming interfaces and ServerStreams configuration
.trunk/trunk.yaml	Downgrades Go runtime version from 1.25.0 to 1.24.1

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