move startup orchestration from mind to event_loop

The top-level run() that creates Mind, wires channels, spawns the
Mind event loop, and starts the UI event loop is orchestration —
it belongs with the UI entry point, not in the cognitive layer.

Renamed to event_loop::start(cli). mind/mod.rs is now purely the
Mind struct: state machine, MindCommand, and the run loop.

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

src/user/mod.rs

@@ -757,7 +757,7 @@ pub async fn main() {
         return;
     }
 
-    if let Err(e) = crate::mind::run(cli).await {
+    if let Err(e) = crate::user::event_loop::start(cli).await {
         let _ = crossterm::terminal::disable_raw_mode();
         let _ = crossterm::execute!(
             std::io::stdout(),