CLI, agent and absorb; stop tracking target/

Every Go command with the same flags, prompts and messages; the agent is
wire-compatible with Go's; tests drive the real Rust and Go binaries.

Co-Authored-By: Claude <noreply@anthropic.com>

src/lib.rs

@@ -6,13 +6,18 @@
 
 #![deny(unsafe_op_in_unsafe_fn)]
 
+pub mod absorb;
+pub mod agent;
+pub mod cli;
 pub mod crypto;
 pub mod error;
 pub mod keyfile;
+pub mod net;
 pub mod pipeline;
 pub mod platform;
 pub mod rng;
 pub mod secret;
 pub mod store;
+#[cfg(test)]
+mod testutil;
 pub mod util;
-pub mod net;