BIM-TechDraw Site Feature Request: There should be a world point for the lat/long/elevation which will also be rendered into TechDraw

### Problem description

The BIM site was an amazing addition to FreeCAD it solves a ton of problems with centralizing project information.

However, there is still two big issues for my BIM use case I will detail my first one here. One is auto aligning the BIM Building model with site data (unless I am completely wrong here). (The second is just that the C++ api doesn't have a nice way to invariantly recognize what Part::FeaturePython is the site object)

Specifically, it is that there is no world space point in the model for the Site that represents the exact latitude/longitude/elevation point. Unless we assume it is 0,0,0 of the .FCStd document but then why would we be selecting objects to be parented by the Site that might not contain 0,0,0. Because that would mean that the Site does not have 0,0,0 of the file in it.

This is a problem since right now the Site is just a general way to say where the project is. But does not detail exactly where that coordinate is for model auto alignment purposes with terrain data upon import.

**It would be nice when the site object is directly selected from the tree view to render a point in the world of that gps coordinates. And to be able to manipulate where that point is for a precise project location. And then also rendered in TechDraw for exact drawing purposes where that point is.**

### Workbench affected?

BIM

### Steps to reproduce

Load BIMExample.FCStd
Select the Site in the tree view (note how 0,0,0 of the grid is not in the objects selected by the site)

### Expected behavior

A Point is rendered where the lat/long is at in the world

### Actual behavior

A Point is not rendered where the lat/long is at in the world

### Development version About Info (in Safe Mode)

```shell
FreeCAD 1.1
Windows 11
```

### Last known good version (optional)

```shell

```

Start with the BIM Site object and the TechDraw workflow described in the issue, using BIMExample.FCStd to inspect the current coordinate behavior. Define how the site's latitude/longitude/elevation point can be represented and manipulated, then verify that selecting the Site renders the point in the model and that TechDraw renders it at the project location.

Written by the indexing model from the issue text.