feat(cmake): Add CMake module (#1456)

* feat: CMake module

* docs: Document symbol variable

src/configs/starship_root.rs

@@ -11,7 +11,7 @@ pub struct StarshipRootConfig<'a> {
 // List of default prompt order
 // NOTE: If this const value is changed then Default prompt order subheading inside
 // prompt heading of config docs needs to be updated according to changes made here.
-pub const PROMPT_ORDER: [&str; 42] = [
+pub const PROMPT_ORDER: [&str; 43] = [
     "username",
     "hostname",
     "singularity",
@@ -26,6 +26,7 @@ pub const PROMPT_ORDER: [&str; 42] = [
     "package",
     // ↓ Toolchain version modules ↓
     // (Let's keep these sorted alphabetically)
+    "cmake",
     "dotnet",
     "elixir",
     "elm",