Remove all mention of unreleased service

[kyoncal]

• Remove every mention of unreleased service in docs and code

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[acmlau]

I don't think we should do a default service string here

[kyoncal]

There needs to be some string as the default service. I suggest the empty string.

[acmlau]

We have https://github.com/aws/aws-mcp-proxy/blob/main/aws_mcp_proxy/utils.py#L54-L83, which ensures we find the correct service string, why can't we leave it without a default? 🤔

[kyoncal]

The service string will indeed be found and replaced after the fact if none is given, however, given that it is a positional argument, if it's not given a default value, one must be provided. Otherwise uses like this won't type check.

[acmlau]

Rather set it to None then empty string

[wzxxing]

Can we make this required, without default parameter? using "" as the signature code will not work. This will help preventing contributors making mistake

[kyoncal]

I think the best solution is to make it optional, since it gets inferred if not explicitly provided by the user anyways. In the latest revision, I've made it more elegant by making the string optional as such.
service: Optional[str] = None,

[kyoncal]

@wzxxing upon further investigation, I believe your solution may be the best. Changing the type from str to Optional[str] is not possible without major refactor. I agree that making it a required argument reduces confusion (albeit a little less elegant).

cc: @acmlau