fix(oidc): do not return access token for response type id_token (#8777)

# Which Problems Are Solved

Do not return an access token for implicit flow from v1 login, if the
`response_type` is `id_token`

# How the Problems Are Solved

Do not create the access token event if if the `response_type` is
`id_token`.

# Additional Changes

Token endpoint calls without auth request, such as machine users, token
exchange and refresh token, do not have a `response_type`. For such
calls the `OIDCResponseTypeUnspecified` enum is added at a `-1` offset,
in order not to break existing client configs.

# Additional Context

- https://discord.com/channels/927474939156643850/1294001717725237298
- Fixes https://github.com/zitadel/zitadel/issues/8776

internal/domain/application_oidc.go

@@ -79,7 +79,8 @@ const (
 type OIDCResponseType int32
 
 const (
-	OIDCResponseTypeCode OIDCResponseType = iota
+	OIDCResponseTypeUnspecified OIDCResponseType = iota - 1 // Negative offset not to break existing configs.
+	OIDCResponseTypeCode
 	OIDCResponseTypeIDToken
 	OIDCResponseTypeIDTokenToken
 )