fix(worktree): abort close when before_remove hook fails to spawn

Show an error in the dialog instead of silently proceeding. The hook
is configured for a reason — if it can't run, the close should stop.

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

Author: neumie

crates/okena-views-git/src/close_worktree_dialog.rs

@@ -434,10 +434,6 @@ impl CloseWorktreeDialog {
             let has_before_remove_hook =
                 project_hooks.worktree.before_remove.is_some() || global_hooks.worktree.before_remove.is_some();
 
-            // Track whether the deferred (PTY) path succeeded so we can fall
-            // through to immediate removal if the hook terminal failed to spawn.
-            let mut deferred = false;
-
             if has_before_remove_hook && runner.is_some() {
                 // Fire hook as visible PTY terminal and defer removal
                 let ok = cx.update(|cx| {
@@ -478,14 +474,19 @@ impl CloseWorktreeDialog {
                         });
                         true
                     } else {
-                        log::warn!("before_worktree_remove hook terminal failed to spawn, falling through to immediate removal");
+                        // Hook terminal failed to spawn — abort, don't remove
+                        let _ = this.update(cx, |this, cx| {
+                            this.error_message = Some("before_worktree_remove hook failed to start".into());
+                            this.processing = ProcessingState::Idle;
+                            cx.notify();
+                        });
                         false
                     }
                 });
-                deferred = ok;
-            }
-
-            if !deferred {
+                if !ok {
+                    return;
+                }
+            } else {
                 // No hook or no runner — run headlessly then remove immediately
                 if has_before_remove_hook {
                     let before_remove_result = smol::unblock({