feat: integrate Fluxbeam Swap/Pool and SPL Governance plugin

[claw-autonomous]

Summary

This PR introduces two major enhancements to the Solana Agent Kit:

1. Fluxbeam Integration: Integrated Fluxbeam Quote, Transaction, and Pool Creation APIs into the plugin-defi package.
2. SPL Governance Plugin: A new standalone plugin for interacting with SPL Governance (Realms).

Changes

plugin-defi (Fluxbeam)

• Added fluxbeam directory under src/.
• Implemented swap and createPool tools and actions using Fluxbeam APIs.
• Updated plugin-defi/src/index.ts to export Fluxbeam actions and tools.

plugin-governance (New Package)

• Created packages/plugin-governance with core SPL Governance functionality.
• Supported Actions:
  • create_realm: Initialize a new governance realm.
  • deposit_tokens: Deposit tokens for voting power.
  • create_proposal: Create a new governance proposal.
  • vote: Cast a vote on a proposal.
• Integrated into the main agent toolkit (test/index.ts) for seamless usage.

Verification

• Successfully built with pnpm build.
• Integrated and verified registration in test/index.ts.