✨ Add native async logger adapter package

examples/async_basic/main.mbt

@@ -0,0 +1,27 @@
+async fn main {
+  let logger = @lib_async.async_logger(
+    @lib.text_console_sink(@lib.text_formatter(show_timestamp=false, separator=" | ")),
+    config=@lib_async.AsyncLoggerConfig::new(
+      max_pending=2,
+      overflow=@lib_async.AsyncOverflowPolicy::DropOldest,
+    ),
+    min_level=@lib.Level::Info,
+    target="async.demo",
+  )
+    .with_timestamp()
+    .with_context_fields([@lib.field("service", "bitlogger")])
+    .with_filter(@lib.target_has_prefix("async"))
+    .with_patch(@lib.compose_patches([
+      @lib.prefix_message("[async] "),
+      @lib.redact_fields(["token"]),
+    ]))
+
+  @async.with_task_group(group => {
+    group.spawn_bg(allow_failure=true, () => logger.run())
+    logger.info("one", fields=[@lib.field("token", "secret")])
+    logger.child("worker").info("two")
+    logger.with_target("skip.demo").info("three")
+    logger.wait_idle()
+    logger.close()
+  })
+}