Modify AuthUI to support linking accounts

[fungc-io]

Figma: https://www.figma.com/file/LRE8EfCaTfYxC0lk5AeMmE/New-Auth-UI?type=design&node-id=2365-15938&mode=design&t=LXscrPWftY0rV2Wc-4

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• Add prompt=login to provider

[linear]

DEV-1204 Modify AuthUI to support merging accounts

[fungc-io]

@tung2744 @louischan @newman see if the design above works?

[fungc-io]

@tung2744 @joyz i've updated the design based on our discussion today. Any thoughts?:
The User will see this if they log in with Google for the 1st time, while it conflicts with an account that contains Email + PW, logged in with GitHub, have passkey set.

[tung2744]

@fungc-io There is a case that the user signed in to a incorrect oauth account after choosing sign in with OAuth. I've created this error message to handle the error, please let me know if any update is needed.

[fungc-io]

Ok 👌

[tung2744]

@fungc-io @louischan Sorry I've found one more problem in this issue. Now the config specify the "action" per linking, which means, the "action" of each conflicted identities could be different if they are conflicted by different linking config. So maybe the message of each button should be different.
As now we actually haven't support login without link, maybe for simplicity we always show "Log in to an existing account to link it", and revise the design later if we supported login without link?

[fungc-io]

maybe for simplicity we always show "Log in to an existing account to link it", and revise the design later if we supported login without link

I agree