User profile: Sanitize inputs/outputs for social media links

[mochet]

Problem

• The input or display fields need to be sanitized so that they are consistent--some users input with an @ prefix and some do not which leads to confusion and inconsistency--there's also nothing currently to stop a user just copy/pasting their full user profile URL (i.e. https://twitter.com/elonmusk)
  

It should be noted that the "end-user" of this data is not just Pioneer, but we also have bots that utilize this data, so it is important for their to be consistency (although technically the bot itself could perhaps handle inconsistencies)

[dmtrjsg]

Scope:
Introduce regex validation for input fields on social media in members profiles