Colorise the inspector output based on S2C or C2S (#242)

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## Description

<!-- Describe the changes you've made. You may include any justification
you want here. -->
I've used the popular `owo-colors` library to colourise the output of
the `packet_inspector`.
This makes it a lot easier to see who's sending what for debugging
purposes.

In future, I'd like to be able to filter out common, low-information
packets like `SetPlayerPosition` and `KeepAlive` as well, but that's not
in this PR.


![image](https://user-images.githubusercontent.com/28905212/218880818-69c0461c-bd23-45c4-9fd4-7c5868be4b67.png)

## Test Plan

No tests - just eyeball 😄.

crates/packet_inspector/Cargo.toml

@@ -7,6 +7,7 @@ description = "A simple Minecraft proxy for inspecting packets."
 [dependencies]
 anyhow = "1"
 clap = { version = "4.0.30", features = ["derive"] }
+owo-colors = "3.5.0"
 regex = "1.6.0"
 tokio = { version = "1", features = ["full"] }
 tracing-subscriber = "0.3.16"

crates/packet_inspector/src/main.rs

@@ -7,6 +7,7 @@ use std::sync::Arc;
 
 use anyhow::bail;
 use clap::Parser;
+use owo_colors::OwoColorize;
 use regex::Regex;
 use tokio::io::{AsyncReadExt, AsyncWriteExt};
 use tokio::net::tcp::{OwnedReadHalf, OwnedWriteHalf};
@@ -58,6 +59,7 @@ struct State {
     read: OwnedReadHalf,
     write: OwnedWriteHalf,
     buf: String,
+    style: owo_colors::Style,
 }
 
 impl State {
@@ -104,7 +106,7 @@ impl State {
             }
         }
 
-        println!("{}", self.buf);
+        println!("{}", self.buf.style(self.style));
 
         Ok(pkt)
     }
@@ -164,6 +166,7 @@ async fn handle_connection(client: TcpStream, cli: Arc<Cli>) -> anyhow::Result<(
         read: server_read,
         write: client_write,
         buf: String::new(),
+        style: owo_colors::Style::new().purple(),
     };
 
     let mut c2s = State {
@@ -173,6 +176,7 @@ async fn handle_connection(client: TcpStream, cli: Arc<Cli>) -> anyhow::Result<(
         read: client_read,
         write: server_write,
         buf: String::new(),
+        style: owo_colors::Style::new().green(),
     };
 
     let handshake: Handshake = c2s.rw_packet().await?;