v0.2.0 - Per‑destination ephemeral identities

- Cache SAM sessions per .i2p domain (reuse identity for all assets on a site)
- 300s idle timeout before session eviction and key wipe
- Dramatically reduces tunnel builds compared to per‑request approach
- Respects I2P network health while maintaining cross‑site unlinkability
- Updated README with new behavior and configuration options

Author: muc111

Cargo.lock

@@ -11,7 +11,7 @@ use tokio::io::{AsyncReadExt, AsyncWriteExt};
 use tokio::net::{TcpListener, TcpStream};
 use tokio::sync::{Mutex, Semaphore};
 use tokio::time;
-use tracing::{debug, error, info, warn};
+use tracing::{debug, error, info};
 use yosemite::{DestinationKind, RouterApi, Session, SessionOptions};
 
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