chore: clean up a bunch of legacy styles (#5973)

* remove unused experimental-styles-within

* remove unused styles

* more cleanup + prepr

* Refactor nearly all legacy buttons to use ButtonStyled

* prepr

* Update MC account selector to modern version

* prepr

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Co-authored-by: Calum H. <calum@modrinth.com>

apps/frontend/src/pages/user/[id].vue

@@ -1,5 +1,5 @@
 <template>
-	<div v-if="user" class="experimental-styles-within">
+	<div v-if="user">
 		<ModalCreation ref="modal_creation" />
 		<CollectionCreateModal ref="modal_collection_creation" />
 		<NewModal ref="editRoleModal" header="Edit role">