fix: use slugs instead of title as basis for explorer (#652)

* use slugs instead of title as basis for explorer

* fix folder persist state, better default behaviour

* use relative path instead of full path as full path is affected by -d

* dont use title in breadcrumb if it's just index lol

quartz/plugins/index.ts

@@ -30,5 +30,6 @@ declare module "vfile" {
   interface DataMap {
     slug: FullSlug
     filePath: FilePath
+    relativePath: FilePath
   }
 }