Scaffold the federated services daemon

Protocol-agnostic core: a Protocol trait maps raw server-to-server lines to a
normalized event/action model, so the engine never touches a raw line and a new
ircd is one new module. Adds event-log state (state is a fold over the log) and
a service framework. First protocol impl links to an InspIRCd (insp4) uplink —
completes the CAPAB/SERVER handshake, bursts, and introduces NickServ.

src/main.rs

@@ -0,0 +1,43 @@
+mod config;
+mod engine;
+mod link;
+mod proto;
+mod services;
+
+use anyhow::Result;
+use std::time::{SystemTime, UNIX_EPOCH};
+
+use engine::Engine;
+use proto::inspircd::InspIrcd;
+use services::nickserv::NickServ;
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    tracing_subscriber::fmt()
+        .with_env_filter(
+            tracing_subscriber::EnvFilter::try_from_default_env()
+                .unwrap_or_else(|_| "fedserv=debug".into()),
+        )
+        .init();
+
+    let path = std::env::args().nth(1).unwrap_or_else(|| "config.toml".to_string());
+    let cfg = config::Config::load(&path)?;
+    let ts = SystemTime::now().duration_since(UNIX_EPOCH)?.as_secs();
+
+    let proto = Box::new(InspIrcd::new(
+        cfg.server.name.clone(),
+        cfg.server.sid.clone(),
+        cfg.uplink.password.clone(),
+        cfg.server.protocol,
+        ts,
+    ));
+
+    let services: Vec<Box<dyn engine::service::Service>> = vec![Box::new(NickServ {
+        uid: format!("{}AAAAAA", cfg.server.sid),
+    })];
+    let engine = Engine::new(services);
+
+    let addr = format!("{}:{}", cfg.uplink.host, cfg.uplink.port);
+    tracing::info!(server = %cfg.server.name, %addr, "linking to uplink");
+    link::run(proto, engine, &addr).await
+}