perf(explorer): client side explorer (#1810)

* start work on client side explorer

* fix tests

* fmt

* generic test flag

* add prenav hook

* add highlight class

* make flex more consistent, remove transition

* open folders that are prefixes of current path

* make mobile look nice

* more style fixes

quartz/components/scripts/util.ts

@@ -37,6 +37,7 @@ export async function fetchCanonical(url: URL): Promise<Response> {
   if (!res.headers.get("content-type")?.startsWith("text/html")) {
     return res
   }
+
   // reading the body can only be done once, so we need to clone the response
   // to allow the caller to read it if it's was not a redirect
   const text = await res.clone().text()