Update example build config and Llama demo to support the new async epoll backend and zigcoro scheduler.

examples/MODULE.bazel

@@ -134,7 +134,6 @@ filegroup(
 )
 use_repo(huggingface, "Meta-Llama-3.2-3B-Instruct")
 
-
 # Llama 3.1
 huggingface.model(
     name = "Meta-Llama-3.1-8B-Instruct",

examples/llama/main.zig

@@ -28,6 +28,7 @@ pub const std_options = .{
         .{ .scope = .zml_module, .level = if (show_mlir) .debug else .warn },
         .{ .scope = .llama, .level = .info },
     },
+    .logFn = asynk.logFn,
 };
 
 pub fn generateText(