feat(keeperhub): add skill for web3 workflow automation via x402

[eskp]

Summary

Adds a skill for KeeperHub (https://app.keeperhub.com) — a web3 workflow-automation platform that exposes DeFi reads, on-chain checks, and tipping primitives as named workflows callable via x402 (USDC on Base, $0.01 typical for reads).

Area	Change
skills/keeperhub/	New CLI-mode skill (mirrors skills/email/ shape)
mcp/skills/keeperhub/	New MCP-mode skill
skills/agentcash/SKILL.md	Add keeperhub to SERVICES + Available Services table; add web3, defi, on-chain to TRIGGERS
mcp/skills/agentcash-wallet/SKILL.md	Same edits
plugin/skills/agentcash/SKILL.md	Same edits

Why now

KeeperHub just hardened its OpenAPI spec for x402/agentcash bazaar discoverability (KeeperHub#1077) — every workflow now declares canonical x-payment-info, extensions.bazaar.schema.{input,output}, security: [] on free routes, and a worked-examples block in info.x-guidance. With the spec corrected, KeeperHub now satisfies the same shape that the curated agentcash preamble assumes, so adding it to SERVICES gives agents a discoverable origin for web3 tasks (currently no listed origin covers DeFi / on-chain).

Workflows surfaced

The Quick Reference table in the new skill lists the live workflows:

Task	Endpoint	Price
Discover workflows (list)	/api/mcp/workflows	Free
Discover workflows (full schema)	/openapi.json	Free
Compare USDC yield (Aave vs Compound)	/api/mcp/workflows/usdc-yield-rates-aave-vs-compound/call	$0.01
Check Aave v3 account health	/api/mcp/workflows/aave-v3-health-check/call	$0.01
Send a micropayment (microtip)	/api/mcp/workflows/microtip/call	$0.01

Verification

Verified against the live KeeperHub OpenAPI spec at https://app.keeperhub.com/openapi.json:

• Workflow path pattern (/api/mcp/workflows/{slug}/call) and response envelope ({executionId, status, output: {result}}) match the canonical spec.
• aave-v3-health-check input ({address}) and output keys (healthFactor, totalCollateralUSD, totalDebtUSD, riskLevel) match.
• usdc-yield-rates-aave-vs-compound input shape ({}) and top-level output keys (rates, bestRate, bestProtocol) match.

Endpoints exercised live (paid settlement on Base) before this PR: ~$0.04 across the three workflows above. All settlements succeeded; the pricing in the table reflects the real x-payment-info.price on each route.

Notes for reviewers

• microtip's input schema is not declared in /openapi.json yet (workflow-side gap on KeeperHub's end, separate from this PR). Rather than invent an example body, the skill directs callers to check_endpoint_schema (MCP) / npx agentcash@latest check (CLI) first. The KeeperHub team has been notified and a backfill is on their side.
• The plugin/ variant only ships the agentcash meta-skill (no per-service skill dirs), matching existing convention — so no plugin/skills/keeperhub/ is added.
• Follows the bavlio (feat(bavlio): add skill for B2B data API via x402 #8) shape for new-service contributions: SKILL.md + rules/getting-started.md, mirrored to mcp/skills/.

Structure

skills/keeperhub/
├── SKILL.md
└── rules/getting-started.md
mcp/skills/keeperhub/
├── SKILL.md
└── rules/getting-started.md

Plus 3-line additions to each of the three top-level agentcash SKILL.md files.