feat: invite user link (#8578)

# Which Problems Are Solved

As an administrator I want to be able to invite users to my application
with the API V2, some user data I will already prefil, the user should
add the authentication method themself (password, passkey, sso).

# How the Problems Are Solved

- A user can now be created with a email explicitly set to false.
- If a user has no verified email and no authentication method, an
`InviteCode` can be created through the User V2 API.
  - the code can be returned or sent through email
- additionally `URLTemplate` and an `ApplicatioName` can provided for
the email
- The code can be resent and verified through the User V2 API
- The V1 login allows users to verify and resend the code and set a
password (analog user initialization)
- The message text for the user invitation can be customized

# Additional Changes

- `verifyUserPasskeyCode` directly uses `crypto.VerifyCode` (instead of
`verifyEncryptedCode`)
- `verifyEncryptedCode` is removed (unnecessarily queried for the code
generator)

# Additional Context

- closes #8310
- TODO: login V2 will have to implement invite flow:
https://github.com/zitadel/typescript/issues/166

internal/auth/repository/eventsourcing/eventstore/user.go

@@ -93,3 +93,41 @@ func (repo *UserRepo) PasswordCodeExists(ctx context.Context, userID string) (ex
 	}
 	return model.exists, nil
 }
+
+type inviteCodeCheck struct {
+	userID string
+
+	exists bool
+	events int
+}
+
+func (p *inviteCodeCheck) Reduce() error {
+	p.exists = p.events > 0
+	return nil
+}
+
+func (p *inviteCodeCheck) AppendEvents(events ...eventstore.Event) {
+	p.events += len(events)
+}
+
+func (p *inviteCodeCheck) Query() *eventstore.SearchQueryBuilder {
+	return eventstore.NewSearchQueryBuilder(eventstore.ColumnsEvent).
+		AddQuery().
+		AggregateTypes(user.AggregateType).
+		AggregateIDs(p.userID).
+		EventTypes(
+			user.HumanInviteCodeAddedType,
+			user.HumanInviteCodeSentType).
+		Builder()
+}
+
+func (repo *UserRepo) InviteCodeExists(ctx context.Context, userID string) (exists bool, err error) {
+	model := &inviteCodeCheck{
+		userID: userID,
+	}
+	err = repo.Eventstore.FilterToQueryReducer(ctx, model)
+	if err != nil {
+		return false, zerrors.ThrowPermissionDenied(err, "EVENT-GJ2os", "Errors.Internal")
+	}
+	return model.exists, nil
+}