[Tests] More consistent naming (#40754)

- [x] **Tests:** Added/updated and all pass
- [x] **Dev docs:** Added/updated

<img width="460" height="1017" alt="image"
src="https://github.com/user-attachments/assets/e72bf221-0875-48c3-b790-4ab1182c7d3a"
/>

I haven't touched the Run module, since we may deprecate it.

Closes: #40788

doc/devdocs/UITests.md

@@ -68,7 +68,7 @@ The PowerToys UI test pipeline provides flexible options for building and testin
 - Pipeline: https://microsoft.visualstudio.com/Dart/_build?definitionId=161438&_a=summary
 
 ## How to add the first UI tests for your modules
-
+- Follow the naming convention: ![{ModuleFolder}/Tests/{ModuleName}-{TestType(Fuzz/UI/Unit)}Tests](images/uitests/naming.png)
 - Create a new project and add the following references to the project file. Change the OutputPath to your own module's path.
   ```
     <Project Sdk="Microsoft.NET.Sdk">