remove most uses of as any in typescript

- replaced many uses of `as any` with another more specific cast `as T`
- filled in missing typed for items that needed to be typed
  - new runtime code was added where necessary to satisfy the new types with comments
- added missing theme variable "sidebar-active" to the Theme variables
- forms using `react-hook-form` are now typechecked
- changed some instances of `target` into `currentTarget` while removing `as any` assertions

src/pages/settings/panes/Sessions.tsx

@@ -155,7 +155,7 @@ export function Sessions() {
                                     ]);
                                     await client.req(
                                         "DELETE",
-                                        `/auth/sessions/${session.id}` as any
+                                        `/auth/sessions/${session.id}` as '/auth/sessions'
                                     );
                                     setSessions(
                                         sessions?.filter(