feat(ethexe): add versioning to contracts, clients

[StackOverflowExcept1on]

Closes #5440
Closes #5463

Summary

This PR adds ability to update protocol version on Router and creates corresponding event that makes graceful join on nodes if version does not match, and also check of protocol version before creation has been added to client constructor.

How to test

cargo build --package ethexe-cli
./target/debug/ethexe run --dev --canonical-quarantine 5
cast send \
  0xCf7Ed3AccA5a467e9e704C703E8D87F634fB0Fc9 \
  "function bumpProtocolVersion(uint8) external" \
  "0" \
  --private-key 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80

2026-06-08T17:49:18.807159Z  INFO ethexe_service: Finalized MB 0xc18d…3165 requests protocol version (1, 0, 0); local client supports (0, 1, 0). Starting graceful shutdown.

Checklist

• PR title follows Conventional Commits (type(scope): description)
• Single logical change
• Tests added or updated (if logic changed)
• Docs updated (if needed)

[gemini-code-assist]

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[breathx]

Remove hard pin to specific version and allow any compatible + bump only version

[StackOverflowExcept1on]

Discussed: we also want version in RPC, and we want to wait for finalization at bump version event