Format pasted JSON in Workflow HttpRequest Action (#15119)

## Context 

The _expected response body_ does not use monaco-editor, so enabling
`formatOnPaste `as mentioned in this
[comment](https://github.com/twentyhq/twenty/issues/13506#issuecomment-3188746787)
didn't fix the issue below. However, the `TextVariableEditor` uses
tiptap editor which has a `handlePaste` option that we can use to format
JSON.
- Issue https://github.com/twentyhq/twenty/issues/13506

## Implementation:

1. Insert the clipboard text at the current selection.
2. Retrieve the full editor content, parse it as JSON and stringify it
with indentation.
3. Re-use the method that transforms the text into `JSONContent`.
4. Replace the root node with the newly formatted `JSONContent`.
5. Update the cursor position based on the type of pasted text.
6. Apply the transaction with `view.dispatch()`

Note: If parsing fails (invalid JSON), the input will fall back to a
normal paste.

## test

Loom:
https://www.loom.com/share/f2e84d078662481f9f9f71fc98b772a1?sid=a649c4e9-8c55-4cbe-b031-7aba60af0e05

packages/twenty-front/src/modules/object-record/record-field/ui/form-types/hooks/useTextVariableEditor.ts

@@ -5,8 +5,10 @@ import HardBreak from '@tiptap/extension-hard-break';
 import Paragraph from '@tiptap/extension-paragraph';
 import Text from '@tiptap/extension-text';
 import { Placeholder, UndoRedo } from '@tiptap/extensions';
+import { AllSelection, TextSelection } from '@tiptap/pm/state';
 import { type Editor, useEditor } from '@tiptap/react';
-import { isDefined } from 'twenty-shared/utils';
+import { isDefined, parseJson } from 'twenty-shared/utils';
+import { type JsonValue } from 'type-fest';
 
 type UseTextVariableEditorProps = {
   placeholder: string | undefined;
@@ -16,6 +18,18 @@ type UseTextVariableEditorProps = {
   onUpdate: (editor: Editor) => void;
 };
 
+/**
+ * Checks if the given text is a valid JSON object (not array, primitive, or null)
+ */
+const isJsonObject = (text: string): boolean => {
+  try {
+    const parsed = JSON.parse(text);
+    return parsed !== null && typeof parsed === 'object';
+  } catch {
+    return false;
+  }
+};
+
 export const useTextVariableEditor = ({
   placeholder,
   multiline,
@@ -68,6 +82,41 @@ export const useTextVariableEditor = ({
         }
         return false;
       },
+      handlePaste: (view, _, slice) => {
+        try {
+          const {
+            state: { schema, tr },
+          } = view;
+          const originalPos = tr.selection.from;
+          const pastedText = slice.content.firstChild?.textContent ?? '';
+
+          // Apply the clipboard text to the document without formatting
+          tr.replaceSelection(slice);
+
+          const newPos = tr.selection.from;
+
+          // Parse the entire document content as JSON and create formatted document node
+          const parsedJson = parseJson<JsonValue>(tr.doc.textContent);
+          const formattedJson = JSON.stringify(parsedJson, null, 2);
+          const formattedDocNode = schema.nodeFromJSON(
+            getInitialEditorContent(formattedJson),
+          );
+
+          // Replace entire document with formatted JSON
+          const rootDocSelection = new AllSelection(tr.doc);
+          tr.setSelection(rootDocSelection);
+          tr.replaceSelectionWith(formattedDocNode);
+
+          // Restore cursor position based on pasted content type
+          const finalPos = isJsonObject(pastedText) ? originalPos : newPos;
+          tr.setSelection(TextSelection.create(tr.doc, finalPos));
+
+          view.dispatch(tr);
+          return true;
+        } catch {
+          return false;
+        }
+      },
     },
     enableInputRules: false,
     enablePasteRules: false,