chore: Clean-up contexts, hooks, & stores

[natalierobbins]

📄 Description

• AuthContext:
  • Instead of using userService, we pull a user's own profile details from AuthContext instead. Because AuthContext already refetches user information on each mount, this deduplicates our original user fetch
  • In order to serve all of the necessary fields, new fields were added to AuthContext's state and actions
• authTokenHandler:
  • Removed old helper functions that are obsolete with introduction of AuthContext.
    • This had some ripple effects into useSurveyStore, which originally imported an initializeSurveyStore function that essentially wipes our store clean. Replaced with clearSession() instead
• useSurveyStore:
  • Removed deprecated keys (employeeName, employeeId, userObjectId) and added new keys to replace our any keyplaceholder
    • We pull these deprecated keys from AuthContext now, instead of storing
• JWT payload:
  • Removed firstName and role fields, which do not support any functionality now that we are re-fetching user regularly

✅ Checklist

• Tests added/updated where needed
• Docs added/updated if applicable
• I have linked the issue this PR closes (if any)

🔗 Related Issues

💡 Type of change

Type	Checked?
🐞 Bug fix	[ ]
✨ New feature	[ ]
📝 Documentation	[ ]
♻️ Refactor	[x]
🛠️ Build/CI	[ ]
Other (explain)	[ ]

🧪 How to test

📝 Notes to reviewers