Revert "Add union link connection type support (#5806)" (#5889)

This reverts commit 8d4e06324f.

comfy_execution/validation.py

@@ -1,32 +0,0 @@
-from __future__ import annotations
-
-
-def validate_node_input(
-    received_type: str, input_type: str, strict: bool = False
-) -> bool:
-    """
-    received_type and input_type are both strings of the form "T1,T2,...".
-
-    If strict is True, the input_type must contain the received_type.
-      For example, if received_type is "STRING" and input_type is "STRING,INT",
-      this will return True. But if received_type is "STRING,INT" and input_type is
-      "INT", this will return False.
-
-    If strict is False, the input_type must have overlap with the received_type.
-      For example, if received_type is "STRING,BOOLEAN" and input_type is "STRING,INT",
-      this will return True.
-    """
-    # If the types are exactly the same, we can return immediately
-    if received_type == input_type:
-        return True
-
-    # Split the type strings into sets for comparison
-    received_types = set(t.strip() for t in received_type.split(","))
-    input_types = set(t.strip() for t in input_type.split(","))
-
-    if strict:
-        # In strict mode, all received types must be in the input types
-        return received_types.issubset(input_types)
-    else:
-        # In non-strict mode, there must be at least one type in common
-        return len(received_types.intersection(input_types)) > 0