refactor(lib): Import tracing macros per-module

Instead of one #[macro_use] at the crate root.

src/client/client.rs

@@ -8,6 +8,7 @@ use futures_util::future::{self, Either, FutureExt as _, TryFutureExt as _};
 use http::header::{HeaderValue, HOST};
 use http::uri::{Port, Scheme};
 use http::{Method, Request, Response, Uri, Version};
+use tracing::{debug, trace, warn};
 
 use super::conn;
 use super::connect::{self, sealed::Connect, Alpn, Connected, Connection};

src/client/conn.rs

@@ -60,6 +60,7 @@ use httparse::ParserConfig;
 use pin_project_lite::pin_project;
 use tokio::io::{AsyncRead, AsyncWrite};
 use tower_service::Service;
+use tracing::{debug, trace};
 
 use super::dispatch;
 use crate::body::HttpBody;

src/client/connect/dns.rs

@@ -31,6 +31,7 @@ use std::{fmt, io, vec};
 
 use tokio::task::JoinHandle;
 use tower_service::Service;
+use tracing::debug;
 
 pub(super) use self::sealed::Resolve;
 

src/client/connect/http.rs

@@ -14,6 +14,7 @@ use http::uri::{Scheme, Uri};
 use pin_project_lite::pin_project;
 use tokio::net::{TcpSocket, TcpStream};
 use tokio::time::Sleep;
+use tracing::{debug, trace, warn};
 
 use super::dns::{self, resolve, GaiResolver, Resolve};
 use super::{Connected, Connection};

src/client/dispatch.rs

@@ -235,6 +235,7 @@ impl<T, U> Callback<T, U> {
         mut when: impl Future<Output = Result<U, (crate::Error, Option<T>)>> + Unpin,
     ) {
         use futures_util::future;
+        use tracing::trace;
 
         let mut cb = Some(self);
 

src/client/pool.rs

@@ -10,6 +10,7 @@ use std::time::{Duration, Instant};
 use futures_channel::oneshot;
 #[cfg(feature = "runtime")]
 use tokio::time::{Duration, Instant, Interval};
+use tracing::{debug, trace};
 
 use super::client::Ver;
 use crate::common::{exec::Exec, task, Future, Pin, Poll, Unpin};

src/client/service.rs

@@ -6,6 +6,8 @@ use std::error::Error as StdError;
 use std::future::Future;
 use std::marker::PhantomData;
 
+use tracing::debug;
+
 use super::conn::{Builder, SendRequest};
 use crate::{
     body::HttpBody,