Sketcher: Implement infinite guide lines for straight lines (similar to circles for arcs), which will help identify connections between constraints and geometry

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Problem description

Currently, the Sketcher includes guide lines for arcs that display the "entire" circle. This is very cool and convenient!


But if an arc (or line) has a "point on line" or "tangent" constraint, and these constraints are located outside the line, it's unclear which line it's connected to.
See the image for a demonstration. I've marked the difficult-to-identify constraints with blue arrows. They just hang in the air.


My proposal:
Implement infinite guide lines for straight lines (similar to circles for arcs), which will help identify connections between constraints and geometry.

Of course, it would be better to make this option disableable, and the guide line type with a choice of thickness and type (for example, a line of 1-pixel dots).

In the image, I simply depicted these lines. Look how much easier it is to understand the constraints. Subtle lines make it much easier to understand the situation.


The option to enable guides could be located in the same place as the grid settings.

@FreeCAD/design-working-group What can you say about this?

### Full version info

```shell
OS: Manjaro Linux (KDE/plasma/xcb)
Architecture: x86_64
Version: 1.1.0dev.20251104 (Git shallow) AppImage
Build date: 2025/11/04 19:07:44
Build type: Release
Branch: main
Hash: af014a1bb44264d749ba9522917f0d1ac76c4bbf
Python 3.11.14, Qt 6.8.3, Coin 4.0.3, Vtk 9.3.1, boost 1_86, Eigen3 3.4.0, PySide 6.8.3
shiboken 6.8.3, xerces-c 3.3.0, IfcOpenShell 0.8.2, OCC 7.8.1
Locale: Russian/Russia (ru_RU)
Navigation Style/Orbit Style/Rotation Mode: Revit/Turntable/Drag at cursor
Stylesheet/Theme/QtStyle: unset/FreeCAD Classic/fusion
Logical DPI/Physical DPI/Pixel Ratio: 96/91.7938/1
Installed mods:
* addFC-main 1.5.1
* CurvedShapes 1.0.14
* SvgWorkbench 1.0.0.dev6
* Reinforcement
* SearchBar 1.8.0 (Disabled)
* SvgWorkbench-main 1.0.0.dev5
* PitchedRoof
* LyapinWorkbrench
* FreeCAD_FastenersWB-master 0.5.42
* FreeCAD_SketchArch-master
* MeshRemodel-master 1.10.38
* FrameForge 0.1.5
* fasteners 0.5.43
* Road 2025.2.22
* MeshRemodel 1.10.38
* addFC 1.9.3
* Curves 0.6.70
* freecad.gears 1.3.0
* CurvedShapesWorkbench-master 1.0.13
* Silk 0.2.0
* sheetmetal 0.7.58
* frame 0.1.1
* OpenTheme 2025.5.20
* Manipulator-master 1.6.3
* FreeCAD_ThreadProfile-master 1.97.0
```

### Subproject(s) affected?

Sketcher

### Anything else?

_No response_

### Code of Conduct

- [x] I agree to follow this project's Code of Conduct