missing py.typed marker to allow dependants to consume types

[graingert]

Currently there are types available, but they are not exported so that they can be used.

Please could you add a py.typed marker file.

[nicholas-johnson-techxcel]

I am newish to python but the average code quality in libraries I find to be shocking. Not using types is unforgivable nowadays.

Just the same concept that nowadays if a senior developer starts a new js project instead of ts, then they are not really senior at all.

I cannot rewrite every library I find to be safe. I did it with firecrawl-py because I had no choice.