Add draft Sign Up V2 end-to-end tests (skipped pending test slice)

[Copilot]

V1 Sign Up E2E coverage had no V2 (server-driven) equivalent for the sign-up flow introduced in PR #3093. This adds the missing suites without duplicating or modifying the production Sign Up V2 logic.

Dependency: stacked on spetrescu/native-auth-v2-signup (PR #3093). Retarget to dev once #3093 merges.

New test suites

• MSALNativeAuthSignUpUsernameV2EndToEndTests.swift — ports all 10 scenarios from V1's MSALNativeAuthSignUpUsernameEndToEndTests onto signUpV2(parameters:delegate:) / MSALNativeAuthSignUpParametersV2 and the unified V2 state machine (MSALNativeAuthCodeRequiredState, AttributesRequiredState/AttributesInvalidState, SignInAfterSignUpState).
• MSALNativeAuthSignUpUsernameAndPasswordV2EndToEndTests.swift — ports all 12 scenarios from V1's MSALNativeAuthSignUpUsernameAndPasswordEndToEndTests.
• SignUpDelegateSpiesV2.swift — new SignUpV2DelegateSpy conforming to the unified MSALNativeAuthFlowDelegate family (CodeRequired, AttributesRequired, AttributesInvalid, SignInAfterSignUpRequired), matching the existing SignInV2DelegateSpy pattern.

Coverage gaps

4 username+password scenarios (...FirstStepAndThenSetPassword..., ...andSetPasswordAfterOTP_success, ...FirstStepAndCustomAttributes..., ...FirstStepAndCustomAttributesOverMultipleScreens...) rely on a post-OTP "set password after verification" step that Sign Up V2 doesn't currently expose. These are kept and marked with // NOTE: comments, adapted to submit the password up front instead — resend-OTP, custom-attribute, and multi-screen coverage is preserved.

Execution

All tests are skipped via:

override func setUpWithError() throws {
    try super.setUpWithError()
    throw XCTSkip("Sign Up V2 requires a test slice. Disable this test until api/test slice is ready.")
}

Sign Up V2 requires a test slice not yet available, so nothing here executes; code was verified to compile against the real V2 API surface.

Project registration

MSAL.xcodeproj/project.pbxproj updated to register the new files under the same group/targets as the V1 sign-up files.

Original prompt

Implement draft Sign Up V2 end-to-end tests in AzureAD/microsoft-authentication-library-for-objc.

Follow the repository's .github/copilot-instructions.md strictly. Work from the current base branch, spetrescu/native-auth-v2-signup, which is the head branch of PR #3093 ("Native Auth V2 (server-driven): sign-up flow"). Do not reimplement or duplicate the production Sign Up V2 logic from that PR.

Objective

Create V2 equivalents of both existing V1 Sign Up E2E suites in one pull request:

1. Existing V1 file:
   MSAL/test/integration/native_auth/end_to_end/sign_up/MSALNativeAuthSignUpUsernameEndToEndTests.swift

   New V2 file and class:
   MSAL/test/integration/native_auth/end_to_end/sign_up/MSALNativeAuthSignUpUsernameV2EndToEndTests.swift
   MSALNativeAuthSignUpUsernameV2EndToEndTests

2. Existing V1 file:
   MSAL/test/integration/native_auth/end_to_end/sign_up/MSALNativeAuthSignUpUsernameAndPasswordEndToEndTests.swift

   New V2 file and class:
   MSAL/test/integration/native_auth/end_to_end/sign_up/MSALNativeAuthSignUpUsernameAndPasswordV2EndToEndTests.swift
   MSALNativeAuthSignUpUsernameAndPasswordV2EndToEndTests

Requirements

• Preserve the corresponding V1 suites' scenario coverage, test intent, setup, and assertions while adapting each flow to the server-driven Sign Up V2 API supplied by PR Native Auth V2 (server-driven): sign-up flow #3093.
• Use the established V2 integration-test patterns already present in the repository, especially:
  • MSALNativeAuthSignInUsernameV2EndToEndTests
  • MSALNativeAuthSignInUsernameAndPasswordV2EndToEndTests
  • MSALNativeAuthSignInWithMFAV2EndToEndTests
  • MSALNativeAuthResetPasswordV2EndToEndTests
• Use appropriate V2 parameters, delegates, continuation states, expectations, error assertions, and Charly Firpo (@mainactor) annotations. Reuse existing helpers/spies when suitable; add narrowly scoped test-only helpers or delegate spies when needed.
• Skip every test at the class level by overriding setUpWithError(), calling try super.setUpWithError(), and then throwing XCTSkip with a clear reason that Sign Up V2 requires a test slice and must remain disabled until that API/test slice is ready.
• Even though class setup skips execution, all test code must compile against the PR Native Auth V2 (server-driven): sign-up flow #3093 branch and comply with repository Swift style and line-length rules.
• Include the standard Microsoft MIT license header in both new files.
• Ensure both files belong to the same integration-test target(s) as their V1 counterparts. Update MSAL/MSAL.xcodeproj/project.pbxproj only if explicit file/target registration is required by the existing project structure.
• Keep this test-only: do not modify production behavior, do not remove or weaken V1 coverage, and do not add a changelog entry.
• Do not execute the Sign Up E2E tests; they require a test slice unavailable in normal execution. Run only the smallest feasible non-E2E compliance checks, such as formatting, SwiftLint, or a compile/build check that does not execute these tests. Do not code sign local builds.

Pull request

• Commit all changes and open exactly one pull request containing both new suites.
• Keep the pull request based on spetrescu/native-auth-v2-signup so it is stacked on PR Native Auth V2 (server-driven): sign-up flow #3093.
• In the PR description, clearly state that PR Native Auth V2 (server-driven): sign-up flow #3093 is a dependency, that all tests are intentionally skipped pending the Sign Up V2 test slice, and that the PR should be retargeted to dev after Native Auth V2 (server-driven): sign-up flow #3093 merges.
• Summarize the V1 scenarios carried forward and any scenario that could not be represented with the current V2 API. Do not silently omit coverage.

[azure-pipelines]

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