fix: improve error handling and create the json encoder once #331 (#332)

* fix: improve error handling for resource closing and JSON encoding in MakeChallenge

* chore: update CHANGELOG with recent changes and improvements

* refactor: simplify RenderIndex function and improve error handling

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Signed-off-by: Jason Cameron <git@jasoncameron.dev>

internal/headers.go

@@ -73,7 +73,7 @@ func NoStoreCache(next http.Handler) http.Handler {
 	})
 }
 
-// Do not allow browsing directory listings in paths that end with /
+// NoBrowsing prevents directory browsing by returning a 404 for any request that ends with a "/".
 func NoBrowsing(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if strings.HasSuffix(r.URL.Path, "/") {