hooks : on_install/on_start/on_stop/on_update globaux (settings.hooks) et par projet (issue #34) - echec non bloquant, dry-run respecte, ordre global puis projet

src/commands/install_cmd.rs

@@ -143,6 +143,11 @@ pub fn run(app: &App, agent_name: &str, method_sel: Option<&str>, force: bool) -
             .with_agent(agent.name.clone())
             .with_args(vec![format!("method={}", method.kind)]),
     );
+    crate::hooks::run_hooks(
+        app,
+        "on_install",
+        &std::env::current_dir().unwrap_or_default(),
+    );
     app.log.success(&format!(
         "installed {} (v{version}) in {}",
         agent.title(),