fix: replace bash_tasks.rs with generic mcp_loose_ends scanner

- hive-ag3nt: remove bash_tasks.rs entirely; add mcp_loose_ends.rs that
  scans harness/mcp-loose-ends/*.json generically (no bash knowledge)
- hive-bash-mcp: daemon writes mcp-loose-ends/bash.json on every task
  state transition (pending/running/done/interrupted/timed_out)
- get_loose_ends: reads mcp_loose_ends::collect() instead of bash-specific code
- implements the generic mechanism from #1162

hive-ag3nt/src/lib.rs

@@ -1,7 +1,6 @@
 //! Shared in-container harness code used by both `hive-ag3nt` (agent) and
 //! `hive-m1nd` (manager) binaries.
 
-pub mod bash_tasks;
 pub mod client;
 pub mod events;
 pub mod forge_notify;
@@ -9,6 +8,7 @@ pub mod identity;
 pub mod login;
 pub mod login_session;
 pub mod mcp;
+pub mod mcp_loose_ends;
 pub mod paths;
 pub mod plugins;
 pub mod prompt;