Bug 313737 – Digital Credentials: align CredentialRequestCoordinator method names with spec algorithm names

• Component: WebCore Misc.
• Status: NEW

[Marcos Caceres]

The CredentialRequestCoordinator's method names and state machine terminology don't match the spec's algorithm names, making it harder to trace spec compliance.

Current → Spec:
- PickerState enum → InteractionState (spec: "interaction states")
- PickerState::Presenting → InteractionState::Requesting (spec: "requesting")
- prepareCredentialRequest() → prepareCredentialRequests() (spec: "prepare credential requests")
- abortPicker() → abortTheCredentialRequest() (spec: "abort the credential request")
- dismissPickerAndSettle() → rejectTheCredentialRequestWith() (spec: "reject the credential request with")
- handleDigitalCredentialsPickerResult() → initiateTheCredentialRequest() (spec: "initiate the credential request")
- showDigitalCredentialsPicker() → showDigitalCredentialsChooser() (spec: "digital credential chooser")
- dismissDigitalCredentialsPicker() → dismissDigitalCredentialsChooser() (spec: "digital credential chooser")

This is a pure mechanical rename with no behavioral changes. Aligning names makes it trivial to cross-reference between spec and implementation and reduces review burden for future spec changes.

Files affected: CredentialRequestCoordinator.h/.cpp, CredentialRequestCoordinatorClient.h, DigitalCredential.cpp, DummyCredentialRequestCoordinatorClient.h/.cpp, DigitalCredentialsCoordinator.h/.cpp/.messages.in, WKDigitalCredentialsPicker.h/.mm, WebPageProxy.h/.cpp, PageClient.h, PageClientImplIOS.h/.mm, PageClientImplMac.h/.mm

Depends on: Meta bug 268516

[Radar WebKit Bug Importer]

<rdar://problem/176128667>

[Marcos Caceres]

Pull request: https://github.com/WebKit/WebKit/pull/64148