Added user phone number and redid login/register flow

[robertyac]

• redid login and register modals layouts
• added phone number field to userProfile model
• added phone number validation (E.164 validation) used for twillio
• added dark mode for phone number field

https://github.com/carsondrobe/Fellas/assets/112982183/59c95eab-17c6-4074-aab1-e96120f2290b

[robertyac]

Tried adding the needed css and javascript for the phone number field at the bottom of modal.html to external documents but it wouldn't work for me.

[robertyac]

Updated client side validation for both forms: