Insert literal replacement text verbatim when use_regex is off (review SE-2)

re.sub always parses the replacement as a template, so a backslash in
the replacement (e.g. C:\1) raised PatternError even in literal mode.
Also drop an unused import and align js import paths with the
documented two-level extension path. Bump to 2.0.13.

js/string_essentials.js

@@ -1,5 +1,5 @@
-import { app } from "../../../scripts/app.js";
-import { ComfyWidgets } from "../../../scripts/widgets.js";
+import { app } from "../../scripts/app.js";
+import { ComfyWidgets } from "../../scripts/widgets.js";
 
 // Consistent sizing for all String Essentials nodes
 const DEFAULT_NODE_WIDTH = 400;

pyproject.toml

@@ -1,7 +1,7 @@
 [project]
 name = "comfyui_stringessentials"
 description = "Simple string manipulation nodes for ComfyUI (strip/remove text strings, search and replace text strings, preview modified string outputs). Useful for modifying text prompts or results from LLM outputs. Nodes will be located under standard Add Node > utils menu. Node names: String Textbox, String Strip, String Multi Replace, String Conditional Append, String Contains Any and String Preview."
-version = "2.0.12"
+version = "2.0.13"
 license = {file = "LICENSE"}
 
 [project.urls]

string_conditional_append_node.py

@@ -1,5 +1,3 @@
-import re
-
 class StringConditionalAppendNode:
     @classmethod
     def INPUT_TYPES(cls):

string_multi_replace_node.py

@@ -95,7 +95,10 @@ class StringMultiReplaceNode:
                     f"StringMultiReplace: invalid regex for search '{search_str}': {e}. "
                     f"Disable use_regex to treat search strings as literal text."
                 )
-            result = regex.sub(replace_str, result)
+            # re.sub always parses the replacement as a template (\1, \g<>);
+            # in literal mode insert the user's text verbatim instead.
+            replacement = replace_str if use_regex else replace_str.replace("\\", "\\\\")
+            result = regex.sub(replacement, result)
 
         if remove_extra_spaces:
             result = self.cleanup_text(result)

test_string_nodes.py

@@ -106,6 +106,20 @@ class TestStringNodes(unittest.TestCase):
         )[0]
         self.assertEqual(result, "Hello everyone")
 
+    def test_replace_literal_backslash_replacement(self):
+        # With use_regex disabled, replacement text is literal: backslash
+        # sequences must not be treated as re.sub group references.
+        result = self.replace_node.string_replace(
+            input_string="path is X",
+            replacement_pairs=r"X::C:\1",
+            replacement_delimiter="::",
+            match_case=False,
+            match_whole_string=True,
+            preserve_punctuation=True,
+            remove_extra_spaces=False
+        )[0]
+        self.assertEqual(result, r"path is C:\1")
+
     def test_replace_multiple_pairs(self):
         input_string = "The quick brown fox jumps over the lazy dog"
         replacement_pairs = """quick::slow