Custom cache id generation at compile time

[bignimbus]

Summary

I'm conveying some requests from side channels into an issue to gather feedback and initial thoughts on this functionality. In short, developers want the ability to get an operation identifier from an external source at compile time and use it as an id in the normalized cache.

Notes

Copying some notes from some offline discussion:

• This section of the Kotlin docs describes the Kotlin API surface area that enables this functionality, so doing something similar would likely meet users' needs
• Would it be easier if they provided the list of queries with their ids and we just took that as the input for codegen?
• We currently output an operation-ids.json file to use to persist queries. But we could take that file as an input just as easily. If there is some build tool that is outputting that information in a standard format from a build tool we could use it

[github-actions]

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