feat: support static debug token

[eljass]

Plugin(s)

• Analytics
• App
• App Check
• Authentication
• Crashlytics
• Cloud Firestore
• Cloud Functions
• Cloud Messaging
• Cloud Storage
• Performance
• Remote Config

Current problem

Currently, on the web, if debug is enabled, Firebase SDK will generate a random debug token that is needed to manually add into the App Check console. With a feature to define static debug token, developer can reuse their once-generated debug token multiple times. This also works when needing to have a working debug token during CI steps.

Preferred solution

Add option to define debug token like Firebase SDK indicates: https://firebase.google.com/docs/app-check/web/debug-provider#:~:text=This%20token%20is%20stored%20locally%20in%20your%20browser%20and%20will%20be%20used%20whenever%20you%20use%20your%20app%20in%20the%20same%20browser%20on%20the%20same%20machine.%20If%20you%20want%20to%20use%20the%20token%20in%20another%20browser%20or%20on%20another%20machine%2C%20set%20self.FIREBASE_APPCHECK_DEBUG_TOKEN%20to%20the%20token%20string%20instead%20of%20true.

Alternative options

No response

Additional context

No response

Before submitting

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• I have attached links to possibly related issues and discussions.