Add Intelica as x402 merchant example — competitive intelligence pay-per-call API

## Summary

[Intelica](https://api.intelica.dev) is a competitive intelligence API that implements x402 v2 and can serve as a reference merchant example for this demo.

It's a real production API with:
- x402Version: 2
- PAYMENT-REQUIRED header with base64 payload
- `eip155:8453` (Base) + `solana:5eykt4...` networks
- Bazaar extension with full input/output schema
- Price: $0.05 USDC per analysis

## Why it fits this repo

This repo demonstrates the seller (CloudFront + Lambda@Edge) side. Intelica is an alternative seller example — a FastAPI service that returns structured JSON rather than static content, showing how x402 works for **API pay-per-call** vs content gating.

Adding Intelica as an optional merchant in the demo would show:

1. Agent sends POST to `https://api.intelica.dev/intel` with `{"text": "startup idea...", "mode": "competitive"}`
2. Receives 402 with PAYMENT-REQUIRED header
3. AgentCore pays $0.05 USDC on Base
4. Receives structured competitive analysis with `action`, `imi_score`, `competitors`

## Reference implementation

Full AgentCore + Intelica example:
https://github.com/teodorofodocrispin-cmyk/Intelica-docs/blob/main/examples/bedrock_agentcore_intelica.py

## Validation

Passed Agentic Market validator: https://agentic.market/validate (paste `https://api.intelica.dev/intel`)

OpenAPI: https://api.intelica.dev/openapi.json

Start by reviewing examples/bedrock_agentcore_intelica.py in the linked Intelica-docs repository, then inspect https://api.intelica.dev/openapi.json and the existing demo structure. Done means Intelica is available as an optional merchant example and demonstrates the documented POST, 402 payment, and structured competitive-analysis response flow.

Written by the indexing model from the issue text.