Implement waitlist status function, hook, and access check for conditional routing

[roman20203]

Description

Implement waitlist status logic for conditional routing based on whether a user is in the waitlist. This includes backend logic, frontend hook, and access checks. We need to fetch the waitlist status (true or false) of a user from Firebase so it can be used as an accessCheck.

Back End Logic:

• Add a Firebase callable function to check if a user is in the waitlist:
• related collection will be named "waitlist-2025" (There is another ticket that is tasked with creating this collection in the Firebase Firestore)
• Relevant file: functions/src/rsvp.ts
• Deploy the function

Front End Hook:

• Create a new hook to fetch the waitlist status of the current user
• src/hooks/useWaitlist

AuthProvider hooks:

• Extend the useUser hook to include the waitlist status

accessCheck:

• Extend the context passed to access check functions to include waitlist status.

Checklist

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