#2 CAP: durable saga compensation + checkpoint heartbeats

[Anonymous]

Originally created by: yaront1111

[Feature] Implement CAP Protocol Extensions: Compensation & Enhanced Heartbeats
Summary
This issue introduces protocol extensions to the CAP (Common Agent Protocol) to support complex financial tasking and granular progress tracking. Specifically, we are adding compensation templates to JobRequest and new checkpoint fields to the Heartbeat message.

Scope
1. Proto Definitions (/sdk/proto)
Compensation: Define a new Compensation message structure and integrate it as an optional field in JobRequest.

Heartbeat Checkpoints: Add progress_pct (float/double) and last_memo (string) to the Heartbeat message to allow agents to report granular status updates.

1. Toolchain & Distribution
   Stubs: Regenerate gRPC/Protobuf stubs for all supported languages: Go, C++, Node.js, and Python.

Documentation: Update /specs, the project Wiki, and inline code examples to reflect the new schema.

Versioning: Bump the SDK version across all package managers.

Technical Notes & Dependencies
Go Vulnerability Management: * The current toolchain uses Go 1.24.0.

govulncheck has identified vulnerabilities in the stdlib (fixed in 1.24.1) and x/net (requires >= 0.23.0). We should address these during the stub regeneration.

Node.js Resolution Issue: * Current npm test fails because the protobuf path is incorrectly resolving to sdk/proto within the dist folder.

Required Fix: Adjust the path resolution logic in the Node.js SDK to correctly point to the source proto files or include them in the build artifact.