refactor: remove InfoBarWidget in favor of plugin-based one

- Replace direct InfoBarWidget with set_info_labels command that emits
  events to plugins
- Replace mini view widget in favor of plugin-based one
- Add widget registry exposure for code-container and editors-container
- Fix DND mixin exec_with_args call (tuple args issue)
- Add break statements in tabs_widget loops for efficiency
- Add _update_transparency call to BaseContainer

plugins/code/info_bar/manifest.json

@@ -0,0 +1,7 @@
+{
+    "name": "Info Bar",
+    "author": "ITDominator",
+    "version": "0.0.1",
+    "support": "",
+    "requests": {}
+}