Use a modern React context for identity in the app (#30098)

app/javascript/mastodon/initial_state.js

@@ -44,12 +44,22 @@
  * @property {string} sso_redirect
  */
 
+/**
+ * @typedef Role
+ * @property {string} id
+ * @property {string} name
+ * @property {string} permissions
+ * @property {string} color
+ * @property {boolean} highlighted
+ */
+
 /**
  * @typedef InitialState
  * @property {Record<string, import("./api_types/accounts").ApiAccountJSON>} accounts
  * @property {InitialStateLanguage[]} languages
  * @property {boolean=} critical_updates_pending
  * @property {InitialStateMeta} meta
+ * @property {Role?} role
  */
 
 const element = document.getElementById('initial-state');