[fix/editor]: generate unique id for text addition

[kaushik552k]

Summary

This PR addresses a bug in the text editor where adding text a second time would not display the new text, even though an empty text entry appeared in the timeline.

Issue Description

• Problem: The text payload contained a static id, causing new text additions to replace the existing text.
• Behavior: On first addition, text is correctly added. On subsequent additions, the timeline shows an empty text (due to the static id) rather than adding a new text element.

Changes Made

• Removed the id from the TEXT_ADD_PAYLOAD.
• Updated the handleAddText function to include id: generateId() so that every call produces a unique id.

How to Test

1. Open the text editor.
2. Add text multiple times.
3. Verify that each text element is added with a unique id and is displayed correctly.