fix jumping cursor bug

[rafaroseira]

Description

Fixes #5870

Fixed an issue in the Table of Contents editor where the cursor would jump to the end of the input field on every keystroke. I modified the following file:

• frontend/src/core/components/tools/editTableOfContents/BookmarkEditor.tsx

Changes

1. Introduced a local state (currentTitleInput) and editingId to decouple text input from the tree re-renders;

2. Implemented a getLatestTree method to synchronize the current title input with the tree state before any changes on the tree (adding/removing/expanding/collapsing nodes or changing target page number);

3. Changed onClick button events to onMouseDown events with preventDefault() to ensure that tree updates trigger before the input focus is lost.

The change (1) was already enough to fix the main bug, but I realized it introduced another bug while I was testing: if the user typed the title input (without clicking outside the text input box) and immediately after clicked on the up and down arrows to change the target page number or clicked on a button (add child/sibling, delete, expand/collapse), then the title input would be restored to its previous state. Hence why I did changes (2) and (3) aswell.

Checklist

General

• I have read the Contribution Guidelines
• I have read the Stirling-PDF Developer Guide (if applicable)
• I have read the How to add new languages to Stirling-PDF (if applicable)
• I have performed a self-review of my own code
• My changes generate no new warnings

Documentation

• I have updated relevant docs on Stirling-PDF's doc repo (if functionality has heavily changed)
• I have read the section Add New Translation Tags (for new translation tags only)

Translations (if applicable)

• I ran scripts/counter_translation.py

UI Changes (if applicable)

• Screenshots or videos demonstrating the UI changes are attached (e.g., as comments or direct attachments in the PR)

Testing (if applicable)

• I have tested my changes locally. Refer to the Testing Guide for more details.