TileMap's GetLocalMousePosition() offsets inside ViewportContainer

### Tested versions

- Reproducible in: v3.5.3 mono stable (latest) as well as v3.5.2 mono stable

### System information

Ubuntu 22.04.4 6.5.0-35-generic

### Issue description

Here, I am trying to create 2 sections, the game on the left side (inside a ViewportContainer) and GUI side panel on the right side.

The values of GetLocalMousePosition() in point A and C should remain the same after the window is resized. This works as intended when the TileMap is on the main Viewport. However, if I wrap the TileMap inside the ViewportContainer, the value offsets unpredictably.


Note: I am not sure if this is a bug

### Steps to reproduce

1. Create a new project with 2D stretch mode and keep aspect.
2. Create the following Main Scene Tree:
```
- HBoxContainer (script)
    - ViewportContainer
        - Viewport
            - TileMap
    - Control
        - ColorRect
        - Label
```
3. Print the coordinate of the GetLocalMousePosition() of the TileMap whenever a LMB is triggered.

### Minimal reproduction project (MRP)

[godot_test_map.zip](https://github.com/user-attachments/files/15935873/godot_test_map.zip)

Start with the attached godot_test_map.zip and reproduce the scene tree using HBoxContainer, ViewportContainer, Viewport, TileMap, and Control nodes. Compare TileMap.get_local_mouse_position() on the main viewport and inside the ViewportContainer while resizing, using the reported mouse-coordinate output; done when the coordinates remain consistent as described.

Written by the indexing model from the issue text.