feat: reusable rule engine to prevent memory reallocation

internal/bench/testdata/proxies/basic-auth.yml

@@ -12,7 +12,7 @@ proxy:
             attributes:
               email: foo@bar.com
         rules:
-          - set_header("Remote-User-Attr-Email", user.attrs.email)
+          - set_header(ctx, "Remote-User-Attr-Email", vars.user.attrs.email)
 fetch:
   url:
     user:

internal/bench/testdata/proxies/queue.yml

@@ -0,0 +1,10 @@
+proxy:
+  from: ["*"]
+  to: ""
+  layers:
+    queue:
+      type: queue
+      enabled: true
+      options:
+        capacity: 100
+        keepAlive: 10s

internal/bench/testdata/proxies/rewriter.yml

@@ -8,5 +8,5 @@ proxy:
       options:
         rules:
           request:
-            - set_host(request.url.host)
-            - set_header("X-Proxied-With", "bouncer")
+            - set_host(ctx, vars.request.url.host)
+            - set_header(ctx, "X-Proxied-With", "bouncer")