feat(cli): add stackbar-mode command

This commit adds a new komorebic command "stackbar-mode" to allow users
to change stackbar modes programmatically.

docs/cli/stackbar-mode.md

@@ -0,0 +1,18 @@
+# stackbar-mode
+
+```
+Set the stackbar mode
+
+Usage: komorebic.exe stackbar-mode <MODE>
+
+Arguments:
+  <MODE>
+          Desired stackbar mode
+          
+          [possible values: always, never, on-stack]
+
+Options:
+  -h, --help
+          Print help
+
+```