dynamically set season / week in UI

[dschuler36]

Plan:

• pull schedule df from nflverse and persist in postgres
• build endpoint that accepts current datetime and returns the active season / week we're in
• ui hits that endpoint on page load and uses it to pull predictions accordingly
• *this assumes that we already have predictions the second the clock ticks to the next week. how to handle that scenario? could fallback to previous week if no predictions? or just put a message that says check back for predictions?

[dschuler36]

closed by #40