Optimize tcp_simple endpoint integration

examples/endpoint_test/Cargo.toml

@@ -10,6 +10,7 @@ include.workspace = true
 [dependencies]
 unshell = { workspace = true }
 leaf-shell = { path = "../../unshell-leaves/leaf-shell" }
+tcp_simple = { path = "../../unshell-leaves/tcp_simple" }
 
 [[bin]]
 name = "endpoint_test"

examples/endpoint_test/src/main.rs

@@ -1,19 +1,27 @@
 #![no_std]
 #![no_main]
 
-extern crate alloc;
+use core::net::Ipv4Addr;
 
 use leaf_shell::{ShellLeaf, ShellState};
+use tcp_simple::TCPServerLeaf;
 use unshell::protocol::{Endpoint, Leaf};
 
 const ID: u32 = 0x12345678;
+const CHILD_ID: u32 = 0x87654321;
 
 #[unsafe(no_mangle)]
 pub fn main(_argc: i32, _argv: *const *const u8) {
     let mut endpoint = Endpoint::new(ID);
+    endpoint.path.push(ID);
+
     let mut shell = ShellLeaf::new(ShellState::new());
+    let mut tcp = TCPServerLeaf::bind_ipv4(Ipv4Addr::LOCALHOST, 1337, CHILD_ID).unwrap();
 
     loop {
+        // One transport tick keeps the minimized binary smaller. Packets read from TCP
+        // are processed by the shell on the next loop, then flushed by this same tick.
         shell.update(&mut endpoint);
+        tcp.update(&mut endpoint);
     }
 }