Add support for nat configuration in gRPC

[mvachhar]

Adds nat configuration options to the expose blocks in gRPC.

Does not Fix #73

[Copilot]

Pull Request Overview

Adds support for NAT (Network Address Translation) configuration in gRPC expose blocks by introducing stateful and stateless NAT types with optional timeout support.

• Introduces new PeeringStatefulNAT and PeeringStatelessNAT message types to the protobuf definition
• Adds a nat oneof field to the Expose message to support both NAT types
• Creates duration conversion utilities for protobuf-to-std time duration handling

Reviewed Changes

Copilot reviewed 7 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/lib.rs	Adds new duration module reference
src/duration.rs	Implements conversion utilities between protobuf and std Duration types
src/bolero/expose.rs	Adds TypeGenerator implementations for NAT types and updates Expose generation
proto/dataplane.proto	Defines new NAT message types and adds nat field to Expose
pkg/dataplane/dataplane.pb.go	Generated Go code for new NAT protobuf messages
build.rs	Updates TypeGenerator configuration for test builds
Cargo.toml	Adds thiserror dependency and bolero dev dependency

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[Copilot]

Pull Request Overview

Copilot reviewed 7 out of 10 changed files in this pull request and generated 3 comments.

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[Frostman]

I'll give a chance @qmonnet to take a look as well as he self-requested review just 2h ago

[qmonnet]

Looks OK to me, thanks!