feat: replace IO type imports with string literals

Remove direct imports of IO type constants from comfy.comfy_types and replace them with string literals "STRING" in input type definitions and return types. This improves code portability and reduces dependency on external type definitions.

Changes made across multiple files:
- Remove `from comfy.comfy_types import IO` imports
- Replace `IO.STRING` with "STRING" in INPUT_TYPES and RETURN_TYPES
- Move CLIPTextEncode import to function scope in prompt.py for better dependency management

This refactor maintains the same functionality while making the code more self-contained and reducing external dependencies.

py/nodes/wanvideo_lora_select.py

@@ -1,4 +1,3 @@
-from comfy.comfy_types import IO # type: ignore
 import folder_paths # type: ignore
 from ..utils.utils import get_lora_info
 from .utils import FlexibleOptionalInputType, any_type, get_loras_list
@@ -16,7 +15,7 @@ class WanVideoLoraSelect:
             "required": {
                 "low_mem_load": ("BOOLEAN", {"default": False, "tooltip": "Load LORA models with less VRAM usage, slower loading. This affects ALL LoRAs, not just the current ones. No effect if merge_loras is False"}),
                 "merge_loras": ("BOOLEAN", {"default": True, "tooltip": "Merge LoRAs into the model, otherwise they are loaded on the fly. Always disabled for GGUF and scaled fp8 models. This affects ALL LoRAs, not just the current one"}),
-                "text": (IO.STRING, {
+                "text": ("STRING", {
                     "multiline": True, 
                     "pysssss.autocomplete": False, 
                     "dynamicPrompts": True, 
@@ -27,7 +26,7 @@ class WanVideoLoraSelect:
             "optional": FlexibleOptionalInputType(any_type),
         }
 
-    RETURN_TYPES = ("WANVIDLORA", IO.STRING, IO.STRING)
+    RETURN_TYPES = ("WANVIDLORA", "STRING", "STRING")
     RETURN_NAMES = ("lora", "trigger_words", "active_loras")
     FUNCTION = "process_loras"