Add "Forgot Password" login option

Users will inevitably forget their passwords. When they do, we need some way to let them recover their account.

Add a small button "Forgot password?" under the main "Log In" button. Then we should look for a UIA flow for /login that looks like this:

• Email login request token
• Email login submit token
• BS-SPEKE enroll OPRF
• BS-SPEKE enroll verify