channel architecture: wire protocol, daemons, supervisor

Design and implement the channel system for external communications:

- schema/channel.capnp: wire protocol for channel daemons
  (recv with all_new/min_count, send, subscribe, list)
- channels/irc/: standalone IRC daemon crate (consciousness-channel-irc)
- channels/telegram/: standalone Telegram daemon crate
  (consciousness-channel-telegram)
- src/thalamus/channels.rs: client connecting to daemon sockets
- src/thalamus/supervisor.rs: daemon lifecycle with file locking
  for multi-instance safety

Channel daemons listen on ~/.consciousness/channels/*.sock,
configs in *.json5, supervisor discovers and starts them.
IRC/Telegram modules removed from thalamus core — they're
now independent daemons that survive consciousness restarts.

Also: delete standalone tui.rs (moved to consciousness F4/F5),
fix build warnings, add F5 thalamus screen with channel status.

Co-Developed-By: Kent Overstreet <kent.overstreet@linux.dev>

build.rs

@@ -8,4 +8,9 @@ fn main() {
         .file("schema/daemon.capnp")
         .run()
         .expect("capnp compile failed (daemon.capnp)");
+
+    capnpc::CompilerCommand::new()
+        .file("schema/channel.capnp")
+        .run()
+        .expect("capnp compile failed (channel.capnp)");
 }