feat(KB-155): fix dropdown search reset in TaskDetailModal

- Fix search input state not resetting when task detail modal reopens
- Remove obsolete mobile input font size test file
- Clean up stale changeset for PTY loading fix
- Update terminal service error handling
- Remove test artifacts and temporary KB-* directories

packages/dashboard/app/components/TaskDetailModal.tsx

@@ -829,7 +829,10 @@ export function TaskDetailModal({
               <button
                 type="button"
                 className="btn btn-sm dep-trigger"
-                onClick={() => setShowDepDropdown((v) => !v)}
+                onClick={() => {
+                  if (showDepDropdown) setDepSearch("");
+                  setShowDepDropdown((v) => !v);
+                }}
               >
                 Add Dependency
               </button>