feat(docs): autogenerate node JSON-RPC API reference from TypeScript source

Adds a generation script that parses the AztecNode and AztecNodeAdmin
interfaces to produce the API reference doc, ensuring it stays in sync
with the actual RPC surface. Fixes missing endpoints (getCheckpointedBlockNumber,
getCheckpointsDataForEpoch, etc.) and removes stale methods.

Author: critesjosh