wip: add tcd sampler

adapted code from https://github.com/comfyanonymous/ComfyUI/pull/3370
TODO: check if virtual scheduler tcd is needed for using sampling_base ModelSamplingDiscreteDistilled or if it's better to use sgm_uniform directly without patching

ldm_patched/contrib/external_model_advanced.py

@@ -70,7 +70,7 @@ class ModelSamplingDiscrete:
     @classmethod
     def INPUT_TYPES(s):
         return {"required": { "model": ("MODEL",),
-                              "sampling": (["eps", "v_prediction", "lcm"],),
+                              "sampling": (["eps", "v_prediction", "lcm", "tcd"]),
                               "zsnr": ("BOOLEAN", {"default": False}),
                               }}
 
@@ -90,6 +90,9 @@ class ModelSamplingDiscrete:
         elif sampling == "lcm":
             sampling_type = LCM
             sampling_base = ModelSamplingDiscreteDistilled
+        elif sampling == "tcd":
+            sampling_type = ldm_patched.modules.model_sampling.EPS
+            sampling_base = ModelSamplingDiscreteDistilled
 
         class ModelSamplingAdvanced(sampling_base, sampling_type):
             pass