README: Add rate limits docs

README.md

@@ -383,6 +383,12 @@ When assembled into a bundle (returned from `AssembleExternalQuote` or `GetExter
 
 See example [`02_external_quote_validation`](examples/02_external_quote_validation/main.go) for an example of using these fields to validate a quote before submitting it.
 
+## Rate Limits
+The rate limits for external match endpoints are as follows: 
+- **Quote**: 100 requests per minute
+- **Assemble**: 5 _unsettled_ bundles per minute. That is, if an assembled bundle is submitted on-chain, the rate limiter will reset. 
+If an assembled match is not settled on-chain, the rate limiter will remove one token from the per-minute allowance.
+
 ## Supported Tokens
 Renegade supports a specific set of tokens for external matches. These can be found at:
 - [Testnet (Arbitrum Sepolia)](https://github.com/renegade-fi/token-mappings/blob/main/testnet.json)