refactor(web_ui): Bus::effective_context_window, sigint_claude + per-connection hello, relocate fetch_reminder_stats, drop redundant guard

hive-ag3nt/src/web_ui/mod.rs

@@ -259,6 +259,17 @@ fn read_gui_vnc_port() -> Option<u16> {
     std::env::var("HIVE_GUI_VNC_PORT").ok()?.parse().ok()
 }
 
+/// SIGINT any running `claude` process in this container (best-effort). Shared
+/// by `/api/cancel` and `/api/logout`. Returns the `pkill` `Output` so callers
+/// can inspect the exit status (0 = signalled, 1 = no process matched) or
+/// ignore it.
+async fn sigint_claude() -> std::io::Result<std::process::Output> {
+    tokio::process::Command::new("pkill")
+        .args(["-INT", "claude"])
+        .output()
+        .await
+}
+
 fn error_response(status: StatusCode, message: &str) -> Response {
     // Plain text — JS app surfaces in `alert()`, HTML wrapping would just
     // be noise. Status is per-caller: 400 for bad input, 409 for a