feat: compute commands

[andrew-virtuals]

Note

Medium Risk
Adds a new on-chain USDC transfer flow for compute top-up, which increases risk due to chain/asset handling and fee calculation, but changes are localized to a new command and API wrapper methods.

Overview
Adds a new acp compute command group with status (fetches compute balance/limit/usage) and top-up (validates amount/chain, computes a fee, sends an on-chain USDC transfer, then notifies the backend with the tx hash).

Extends the Agent API client with compute types and endpoints (/agents/:id/compute/account, /common/compute-fee, /agents/:id/compute/top-up), wires the command into the CLI entrypoint, and updates README.md/SKILL.md docs to include the new compute workflow.

^{Reviewed by Cursor Bugbot for commit ae12288. Bugbot is set up for automated code reviews on this repo. Configure here.}

[cursor]

Cursor Bugbot has reviewed your changes and found 2 potential issues.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit ae12288. Configure here.}