story-kit: merge 298_story_bot_htop_command_with_live_updating_process_dashboard

Adds htop bot command with live-updating Matrix message showing system
load and per-agent CPU/memory usage. Supports timeout override and
htop stop. Resolved conflict with git command in commands.rs registry.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/src/matrix/mod.rs

@@ -18,6 +18,7 @@
 mod bot;
 pub mod commands;
 mod config;
+pub mod htop;
 pub mod notifications;
 
 pub use config::BotConfig;