[PM-11949] Fix generating and copying export password (#10999)

* Use password field value instead of local variable for copy to clipboard

Use appCopyClick directive instead of manually copying and showing success toast

* Add missing "copySuccessful" message key to desktop and web

* Remove whitespace from web en/messages.json

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Co-authored-by: Daniel James Smith <djsmith85@users.noreply.github.com>

apps/desktop/src/locales/en/messages.json

@@ -1285,6 +1285,9 @@
       }
     }
   },
+  "copySuccessful": {
+    "message": "Copy Successful"
+  },
   "errorRefreshingAccessToken": {
     "message": "Access Token Refresh Error"
   },

apps/web/src/locales/en/messages.json

@@ -562,6 +562,9 @@
       }
     }
   },
+  "copySuccessful": {
+    "message": "Copy Successful"
+  },
   "copyValue": {
     "message": "Copy value",
     "description": "Copy value to clipboard"