Accept UserId type parameter in convexAdapter

[ozanmakes]

BetterAuth class accepts a type parameter UserId. However if used, it causes a type error when passing it to convexAdapter because this function only accepts BetterAuth

This change fixes code such as the following:

export const betterAuthComponent = new BetterAuth<Id<"users">>(components.betterAuth, {
  authFunctions,
  publicAuthFunctions,
});

// ...

betterAuth({
    database: convexAdapter(ctx, betterAuthComponent),
    ...
})

Before this would give the type error

Argument of type 'BetterAuth<Id<"users">>' is not assignable to parameter of type 'BetterAuth<string>'.
  Types of property 'createAuthFunctions' are incompatible.

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