[Sessions] Initial commit of Firebase Sessions SDK

[samedson]

Paired with: @jeremyjiang-dev

Notes

• We haven't setup any SDKs with the Sessions SDK as a dependency, so this should not go out to users (unless they specify it directly)
• We've only setup CocoaPods so far (for development), not SPM

Questions

• We were using FunctionsComponent.swift as a reference. We see there is a protocol and initializer there. Our protocol isn't being called, and I'm not sure where their functions(... protocol method is being called
  • Is the protocol needed?
  • It looks like it's needed as something to pass into the Component constructor

#no-changelog
#sessions

[ncooke3]

Still working through the DD... but here's a first pass!

[samedson]

Thanks for the suggestions @ncooke3 ! Added my responses.

[ncooke3]

CI should be fixed by a rebase on top of master.

[ncooke3]

@samedson, sorry– I thought the rebase would surely fix CI. It's not a blocker though since the failure is unrelated.

[samedson]

Sounds good - thanks for the advice! I made one change to include a reference to the Google App ID because we'll need that

[paulb777]

While starting with CocoaPods is ok, it might be better to do early development in Swift Package Manager, since it's the future.