route breadcrumbs, improve sidebar, basic folder layout

components/ui/collapsible/Collapsible.vue

@@ -0,0 +1,19 @@
+<script setup lang="ts">
+import type { CollapsibleRootEmits, CollapsibleRootProps } from 'reka-ui'
+import { CollapsibleRoot, useForwardPropsEmits } from 'reka-ui'
+
+const props = defineProps<CollapsibleRootProps>()
+const emits = defineEmits<CollapsibleRootEmits>()
+
+const forwarded = useForwardPropsEmits(props, emits)
+</script>
+
+<template>
+  <CollapsibleRoot
+    v-slot="{ open }"
+    data-slot="collapsible"
+    v-bind="forwarded"
+  >
+    <slot :open="open" />
+  </CollapsibleRoot>
+</template>