chore(auth): Refactor to eliminate circular dependencies

[cshfang]

Description of changes

Prior to [email protected], analyzing the Auth package for circular dependencies yields no issues:

$ git checkout [email protected]
$ npx dpdm -T --no-tree --no-warning packages/auth/src/index.ts

✅ Congratulations, no circular dependency was found in your project.

With the introduction of [email protected], the same analysis shows circular dependencies were introduced:

$ git checkout [email protected]
$ npx dpdm -T --no-tree --no-warning packages/auth/src/index.ts

1) packages/auth/src/providers/cognito/utils/signInHelpers.ts -> packages/auth/src/client/flows/userAuth/handleWebAuthnSignInResult.ts
2) packages/auth/src/providers/cognito/utils/signInHelpers.ts -> packages/auth/src/client/flows/shared/handlePasswordSRP.ts
3) packages/auth/src/providers/cognito/utils/signInHelpers.ts -> packages/auth/src/client/flows/userAuth/handleSelectChallengeWithPassword.ts
4) packages/auth/src/providers/cognito/utils/signInHelpers.ts -> packages/auth/src/client/flows/userAuth/handleSelectChallengeWithPasswordSRP.ts

This PR extracts functions from the monolithic signInHelpers to eliminate the circular dependencies

$ git checkout chore/eliminate-circular-dependencies
$ npx dpdm -T --no-tree --no-warning packages/auth/src/index.ts

✅ Congratulations, no circular dependency was found in your project.

Issue #, if available

#14150

Description of how you validated changes

• Ran the dpdm analyzer to ensure the Auth entry point no longer resulted in circular dependencies.
• Published changes locally to Verdaccio and ran the Webauthn E2E tests
• yarn test

Checklist

• PR description included
• yarn test passes
• Unit Tests are changed or added
• Relevant documentation is changed or added (and PR referenced)

Checklist for repo maintainers

• Verify E2E tests for existing workflows are working as expected or add E2E tests for newly added workflows
• New source file paths included in this PR have been added to CODEOWNERS, if appropriate

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[jjarvisp]

Looks good to me. Is it worth adding a test to check for circular dependencies in the future?