Move SpacetimeDB Token to httpOnly Cookie Instead of LocalStorage

[Lethalchip]

In order to make this change without breaking, we need to:

1. Read httpOnly cookie for Token, check LocalStorage if no cookie exists
2. Set a httpOnly cookie, remove setting of LocalStorage Token

In useStDB.tsx

Should we look to move the other localstorage items into a cookie? Realistically, the only sensitive info is the StDB token.