fix an issue that image is not showen in precise wall wiki

doc/Precise-wall.md

@@ -3,8 +3,8 @@ The 'Precise Wall' is a distinctive feature introduced by OrcaSlicer, aimed at i
 Below is a technical explanation of how this feature works. 
 First, it's important to understand some basic concepts like flow, extrusion width, and space. Slic3r has an excellent document that covers these topics in detail. You can refer to this article: [link to article](https://manual.slic3r.org/advanced/flow-math).
 
-Now, let's dive into the specifics. Slic3r and its forks, such as PrusaSlicer, SuperSlicer, and OrcaSlicer, assume that the extrusion path has an oval shape, which accounts for the overlaps. For example, if we set the wall width to 0.4mm and the layer height to 0.2mm, the combined thickness of two walls laid side by side is 0.714mm instead of 0.8mm due to the overlapping.
-![image](https://github.com/SoftFever/OrcaSlicer/assets/103989404/924d8df8-992c-4d55-b97d-fb85455fab5b)
+Now, let's dive into the specifics. Slic3r and its forks, such as PrusaSlicer, SuperSlicer, and OrcaSlicer, assume that the extrusion path has an oval shape, which accounts for the overlaps. For example, if we set the wall width to 0.4mm and the layer height to 0.2mm, the combined thickness of two walls laid side by side is 0.714mm instead of 0.8mm due to the overlapping. 
+![image](./images/precise_wall.png) 
 This approach enhances the strength of 3D-printed parts. However, it does have some side effects. For instance, when the inner-outer wall order is used, the outer wall can be pushed outside, leading to potential size inaccuracy and more layer inconsistency.
 
 It's important to keep in mind that this approach to handling flow is specific to Slic3r and it's forks. Other slicing software, such as Cura, assumes that the extrusion path is rectangular and, therefore, does not include overlapping. Two 0.4 mm walls will result in a 0.8 mm shell thickness in Cura