fix: add missing packages

Author: frankpagan

package.json

@@ -60,6 +60,7 @@
   },
   "dependencies": {
     "@cocreate/docs": "^1.0.3",
+    "@cocreate/observer": "^1.0.2",
     "mini-css-extract-plugin": "^1.5.0"
   }
 }

yarn.lock

@@ -841,6 +841,14 @@
     parse-html-comments "^1.3.1"
     ws "^7.3.1"
 
+"@cocreate/observer@^1.0.2":
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/@cocreate/observer/-/observer-1.0.2.tgz#b29cb1db6fc78f533b8c53e1b97a221065413bd6"
+  integrity sha512-Lml118xYD+sXL/N7vc+hUcir0dm5OvVch/VD+TI53sIULDin9w1aP0tvcwD90yEzenPlkJ7luLD7/Yf9ARnrAg==
+  dependencies:
+    "@cocreate/docs" "^1.0.3"
+    mini-css-extract-plugin "^1.5.0"
+
 "@discoveryjs/json-ext@^0.5.0":
   version "0.5.2"
   resolved "https://registry.yarnpkg.com/@discoveryjs/json-ext/-/json-ext-0.5.2.tgz#8f03a22a04de437254e8ce8cc84ba39689288752"