feat: locations tree viewer (#248)

* location tree API

* test fixes

* initial tree location elements

* locations tree page

* update meta-data

* code-gen

* store item display preferences

* introduce basic table/card view elements

* codegen

* set parent location during location creation

* add item support for tree query

* refactor tree view

* wip: location selector improvements

* type gen

* rename items -> search

* remove various log statements

* fix markdown rendering for description

* update location selectors

* fix tests

* fix currency tests

* formatting

frontend/components/Location/Tree/tree-state.ts

@@ -0,0 +1,17 @@
+import type { Ref } from "vue";
+
+type TreeState = Record<string, boolean>;
+
+const store: Record<string, Ref<TreeState>> = {};
+
+export function newTreeKey(): string {
+  return Math.random().toString(36).substring(2);
+}
+
+export function useTreeState(key: string): Ref<TreeState> {
+  if (!store[key]) {
+    store[key] = ref({});
+  }
+
+  return store[key];
+}