Can't Add Frameworks (specifically Firestore/Firebase Auth) To App Extension Target

I have been unable to add Firebase/FirebaseAuth or anything else to my app extension target which is embedded in my Project. At first I tried adding the frameworks from clicking on the Target and adding to frameworks and libraries. However, I was unable to get a reference in my extension target... just my main app.

My Podfile is below. Without using Cocoapods, I can't get a reference to Firebase, but with Cocoapods I get errors like:

FBSDKCoreKit/FBSDKLoginKit from Firebase pod?: 'sharedApplication' is unavailable: not available on iOS (App Extension)

...and other "semantic" errors. In the case of the FBSDK, I'm not even using that unless it comes with Firebase, which I can't seem to find the details of.

Anyone have any ideas on how I can cleanly just put my database input code in my INSendMessageIntent... it's really that simple... I have to be overthinking this, right?

I've tried cleaning the build folder, deleting derived data, deleting podfile/pods/workspace/podfile.lock, clearing pod cache, redoing all of it, etc, etc, etc...

Code Block 
target 'UpdateMessages' do
  # Comment the next line if you don't want to use dynamic frameworks
  use_frameworks!
  # Pods for UpdateMessages
#pod 'Firebase/Auth'
#pod 'Firebase/Firestore'
end