feat: connect SSO after login (closes #52)

[kimlimjustin]

Giving the ability for users to connect their SSO after creating accounts using passwords, simply by going to the account page and click the button "Link my account with [provider]"

^ Example with google as a provider

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[kimlimjustin]

I have read the CLA Document and I hereby sign the CLA

[kimlimjustin]

recheck

[zicklag]

Awesome, thanks, just a couple review notes.

Also, we should probably add a way to disconnect a provider soon after this.

[kimlimjustin]

Thanks for the fast response, it was my bad and I've edited them.

Also, we should probably add a way to disconnect a provider soon after this.

In my mind, we'll also need the option to add a password for an SSO-registered account too, wdyt? I'll probably send another PRs regarding this asap

[zicklag]

In my mind, we'll also need the option to add a password for an SSO-registered account too, wdyt? I'll probably send another PRs regarding this asap

Yeah, definitely.

I think the way it works in Rauthy is:

• If you're connected to an SSO provider, you can click a button to disconnect, and it will send you a password reset email to set your password.
• If you aren't connected to an SSO provider, then it shows the buttons to connect to one ( like you have it already with this PR )

That means you can only connect to one provider at a time, which is how Rauthy works I think.

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Oh, one other thought, it'd be good to have the logos for the SSO providers to connect to in the link buttons.

But I'll merge this now, thanks again!