feat: 🎸 filter sessions by status & scope (#2058)

* feat: 🎸 filter sessions by status

✅ Closes: https://hashicorp.atlassian.net/browse/ICU-12067

addons/api/addon/models/target.js

@@ -108,6 +108,14 @@ export default class TargetModel extends GeneratedTargetModel {
       .filter((s) => s && s.target_id === this.id);
   }
 
+  /**
+   * Available sessions associated with this target (but only already loaded sessions).
+   * @type {SessionModel[]}
+   */
+  get availableSessions() {
+    return this.sessions.filter((session) => session.isAvailable);
+  }
+
   /**
    * The project associated with this target (if already loaded).
    * @type {ScopeModel}