fix: min-window-size setting now read live from Gio.Settings on every boundary adjust

Previously _minRatio was baked into WindowContainer at construction time
and never updated. Now adjustBoundary() takes minRatio as a parameter,
WindowManager._getMinRatio() reads it from Gio.Settings on every call,
and the settings reference is injected from extension.ts on enable().

extension.ts

@@ -20,6 +20,7 @@ export default class aerospike extends Extension {
 
     enable() {
         Logger.log("STARTING AEROSPIKE!")
+        this.windowManager._settings = this.settings;
         this.bindSettings();
         this.setupKeybindings();
         this.windowManager.enable()