Add initWithServiceName:resourceName:baseURL:APIKey:requestHooks:
debugToken: (Swift: init(serviceName:resourceName:baseURL:apiKey:
requestHooks:debugToken:)) to GACAppCheckDebugProvider so callers can
supply a debug token resolved outside the SDK, such as one the Firebase
CLI saved to ~/.config/configstore/firebase-appcheck.json. The existing
initializer delegates to it with a nil token.
Tokens resolve in this order: the AppCheckDebugToken or
FIRAAppCheckDebugToken environment variable, the provided token, the
stored local token, then a newly generated one. The provided token is
trimmed, and an empty result falls back to the local token. When it is
used, no local token is generated, stored, or logged; a debug-level
message (I-GAC004005) is logged instead, and its exchanges don't change
the local token's registered state.
Also add debugTokenSource and AppCheckCoreDebugTokenSource
(GACAppCheckDebugTokenSource: local, environmentVariable, provided),
which report where the current token came from. The enum is Sendable
and marked @nonexhaustive when the compiler supports it, so new sources
can be added without breaking Swift clients.
For consistency, renamed both instanceName and storageID to serviceName for consistency.
In all cases, the serviceName is an identifier that differentiates multiple GACAppCheck instances such as when there are multiple FIRApps in use, or multiple dependent SDKs (e.g., Firebase and Google Sign-In). This unique identifier ensures their state is not shared in the Keychain or in User Defaults.
Made the tokenDelegate parameter nullable in the constructor for GACAppCheck since the feature is not used by all integrators. E.g., it is not needed if token refresh isn't used -- 'tokenDidUpdate:instanceName:' would never get called.
- Added parameter documentation to the 'initWithInstanceName:appCheckProvider:settings:tokenDelegate:resourceName:keychainAccessGroup' constructor in GACAppCheck.
- Renamed the umbrella header from AppCheck.h to AppCheckCore.h to match the framework name.
