FRE-600: Fix code review blockers

- Consolidated duplicate UndoManagers to single instance
- Fixed connection promise to only resolve on 'connected' status
- Fixed WebSocketProvider import (WebsocketProvider)
- Added proper doc.destroy() cleanup
- Renamed isPresenceInitialized property to avoid conflict

Co-Authored-By: Paperclip <noreply@paperclip.ing>

node_modules/eslint/lib/rules/no-delete-var.js

@@ -0,0 +1,42 @@
+/**
+ * @fileoverview Rule to flag when deleting variables
+ * @author Ilya Volodin
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+/** @type {import('../shared/types').Rule} */
+module.exports = {
+    meta: {
+        type: "suggestion",
+
+        docs: {
+            description: "Disallow deleting variables",
+            recommended: true,
+            url: "https://eslint.org/docs/latest/rules/no-delete-var"
+        },
+
+        schema: [],
+
+        messages: {
+            unexpected: "Variables should not be deleted."
+        }
+    },
+
+    create(context) {
+
+        return {
+
+            UnaryExpression(node) {
+                if (node.operator === "delete" && node.argument.type === "Identifier") {
+                    context.report({ node, messageId: "unexpected" });
+                }
+            }
+        };
+
+    }
+};