feat: use undecoded @path and @query according to the spec (#4)

Author: AlexanderTar

src/httpbis/index.ts

@@ -93,7 +93,9 @@ export function deriveComponent(component: string, params: Map<string, string |
                 throw new Error('Cannot derive @scheme on response');
             }
             const { pathname } = typeof context.url === 'string' ? new URL(context.url) : context.url;
-            return [decodeURI(pathname)];
+            // https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-message-signatures#section-2.2.6
+            // empty path means use `/`
+            return [pathname || '/'];
         }
         case '@query': {
             if (!isRequest(context)) {
@@ -102,7 +104,7 @@ export function deriveComponent(component: string, params: Map<string, string |
             const { search } = typeof context.url === 'string' ? new URL(context.url) : context.url;
             // https://datatracker.ietf.org/doc/html/draft-ietf-httpbis-message-signatures#section-2.2.7
             // absent query params means use `?`
-            return [decodeURI(search) || '?'];
+            return [search || '?'];
         }
         case '@query-param': {
             if (!isRequest(context)) {