Add Base Voucher plugin for ETH/USDC gift cards on Base

[Surya512002]

Description

Adds Base Voucher — a hybrid Base MCP plugin for creating and redeeming ETH/USDC crypto gift cards on Base mainnet.

• Prepare: Base Voucher MCP at https://base-analytics-app.vercel.app/api/mcp
  • Tools: voucher_prepare_create, voucher_prepare_redeem, voucher_lookup_batch
• Execute: Base MCP send_calls on chain base
• Fallback: GET prepare endpoints on base-analytics-app.vercel.app

Live app: https://base-analytics-app.vercel.app
Agent API smoke test: 16/16 pass on production.

Allowlist request: Please add base-analytics-app.vercel.app to the Base MCP web_request allowlist for HTTP fallback on chat-only surfaces.

Type of change

• Base MCP plugin submission

Affected skill(s)

• base-mcp

Plugin checklist

• Plugin spec/manifest is accurate and tested
• API endpoints and external MCP tested and functional
• Follows Contribution Scope (single plugin file only; no SKILL.md edit)

Base MCP Plugin Submission Agreement

• I have read and agree to the Base MCP Plugin Submission Agreement above.

Test plan

• GET /api/voucher/prepare-create?asset=USDC&total=10&cards=5&creator=0x... → valid:true, calls[], cards[]
• MCP tools/list at /api/mcp → 3 voucher tools
• End-to-end create + redeem tested via Base MCP send_calls

[cb-heimdall]

🟡 Heimdall Review Status

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