chore: Add comments to public methods

- rename GetRepo to GetDirectoryForRegisteredRepo so it's actually doing what it says

build/BuildContext.cs

@@ -33,7 +33,17 @@ public class BuildContext : FrostingContext
 	/// </summary>
 	public ConvertableFilePath CreateModuleManifestScript { get; set; }
 
+	/// <summary>
+	/// Suffix to tag the build with, defaults to pre-release.
+	/// <para>
+	/// Immediately follows the version number and before the commit hash.
+	/// </para>
+	/// </summary>
 	public string BuildSuffix { get; set; }
+
+	/// <summary>
+	/// Disable the commit hash from being added
+	/// </summary>
 	public bool DisableCommitHash { get; set; }
 
 	public BuildContext(ICakeContext context)
@@ -45,7 +55,7 @@ public class BuildContext : FrostingContext
 		PowershellModuleOutputDir = context.Directory("../") + context.Directory("output") + context.Directory("PowershellModule");
 		var buildScriptDirectory = context.Directory("./Scripts");
 		CreateModuleManifestScript = buildScriptDirectory + context.File("CreateModuleManifest.ps1");
-		BuildSuffix = context.Configuration.GetValue(nameof(BuildSuffix));
+		BuildSuffix = context.Configuration.GetValue(nameof(BuildSuffix)) ?? "pre-release";
 		DisableCommitHash = context.Configuration.GetBoolValue(nameof(DisableCommitHash));
 	}
 }