[Feature] Update Events Page: RSVP Feature, Upcoming/Past Events, Event Details

**Describe new addition**
Allow users to RSVP to an upcoming event, view current and upcoming events, and interact with events (view details, add to Calendar, etc.)

**Task List**
- [ ] Build an Event Component to display Events (Past, Current, and Upcoming) on the portal.
- [ ] Refactor Event data on Firebase to store RSVP attendees
- [ ] Link events that have been RSVP to a user's profile
- [ ] Build *Event Type* Sections Component
- [ ] Configure Events Display to Filter by available sections (Upcoming, Past, etc.)

**Notes**
- Describe the architecture of this component in the Project Documentation. Be sure to specify certain UX decisions and the general structure of the page. Keep in mind upcoming design changes.

**Potential Upgrades**
Hooking *Event Details* to a potential **ACM Events** Calendar may make managing and deploying this service more feasible and customizable.

Locate the Events page and event-related components in the portal, then trace where Firebase event data is read and written to confirm the current schema. Next inspect user-profile persistence paths to connect RSVP relationships and find where upcoming/current/past filtering logic is implemented. Finally, update Project Documentation with the event architecture and UX decisions; done means event sections render correctly, RSVPs persist in Firebase for users/events, and the flow is documented.

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