Document authorization requirements for RPC endpoints

[simone-stacks]

Problem

Some RPC endpoints require authorization headers but this isn't documented in our OpenAPI specification. For example, the GET /v3/blocks/replay/{block_id} endpoint returns a 401 error when authorization is missing, but the OpenAPI spec doesn't include this response code.

Proposed Solution

1. Create a testing script that calls each RPC endpoint to determine what works and what doesn't
2. Document which endpoints return 401 errors
3. Update the OpenAPI specification