fix: pass url string to URLPattern.exec() in dynamic route matching

Deno's URLPattern implementation runs
webidl.converters["URLPatternInput"] when exec() receives a URL object.
That conversion walks the object's properties on every call and happens
before the internal match cache is consulted, so the cache never helps.
Passing the serialized url skips the conversion layer entirely and hits
the cache directly.

Measured with 6 route patterns, median of 5 rounds x 100k calls:

- Deno 2.9.0 (aarch64-darwin): 4348 -> 221 ns/call (~19.7x)
- Node 24.18.0 (native URLPattern): 2376 -> 1220 ns/call (~1.9x)

The win is specific to runtimes with a JS-based URLPattern (Deno); on
runtimes with a native implementation there is no regression. Reading
url.href costs ~2ns because URL objects cache their serialization.

Refs #1931

Author: SisyphusZheng

packages/fresh/src/router.ts

@@ -158,7 +158,14 @@ export class UrlPatternRouter<T> implements Router<T> {
     for (let i = 0; i < this.#dynamicArr.length; i++) {
       const route = this.#dynamicArr[i];
 
-      const match = route.pattern.exec(url);
+      // Pass `url.href` instead of the `URL` object: ~13-21x faster.
+      // Deno's URLPattern is a pure JS implementation. Given a `URL` object,
+      // `webidl.converters["URLPatternInput"]` walks and converts its
+      // properties on every call, and this happens *before* the internal
+      // match cache is consulted — so the cache never helps. A string skips
+      // that conversion entirely. `URL` objects cache their serialization,
+      // so reading `.href` here costs ~3ns.
+      const match = route.pattern.exec(url.href);
       if (match === null) continue;
 
       result.pattern = route.pattern.pathname;