Plugin doesn't handle `cmake.sourceDirectory` changes properly

Brief Issue Summary

I have a workspace structure that looks like this:

.
├── cmake-simple-demo
│   └── CMakeLists.txt
├── cmake-simple-demo_copy
│   └──  CMakeLists.txt
└──  cmake-simple-demo_copy_1
    └──  CMakeLists.txt

When VSCode is first opened, the CMake view is not listed under "Open View" and many CMake commands are missing. This is to be expected, since the default value of cmake.sourceDirectory is ${workspaceFolder}, but there is no CMakeLists file there. However, when I give the preference a value, the commands are still missing, and the CMake view is still not listed. They only show once I reload the IDE.

A related issue: when there is only 1 path in the cmake.sourceDirectory array, the path and name of the folder is automatically assumed to be the workspace folder, which is not always true.

Related again: when there is an array of directories in the array, and one new entry is added, the path and name of the folder is also assumed to be the workspace folder. This is fixed on reload, and also does not occur if more than 1 entry is added at once.

CMake Tools Diagnostics

Debug Log

Additional Information

I did some preliminary digging. The second issue is caused by this line: https://github.com/microsoft/vscode-cmake-tools/blob/main/src/projectController.ts#L279. It should instead always return this.sourceDir.

The last issue is caused by this line: https://github.com/microsoft/vscode-cmake-tools/blob/main/src/projectController.ts#L279. The parameter value only includes the newly added values, hence why checking for length > 1 is incorrect.

I wanted to make sure there weren't any edge cases I was missing making these changes. For example, CMakeProject.folderPath has a comment that says "For single-project folders, this is the WorkspaceFolder for historical reasons." I haven't looked at the first issue yet.

Start in src/projectController.ts around line 279 and review the CMakeProject.folderPath comment about single-project folders. Reproduce changing cmake.sourceDirectory from an invalid default and adding one directory at a time, then verify the CMake view and commands update without reloading and folder paths remain correct. Check the related project-controller behavior for edge cases before defining the fix.