Russh: Post-auth remote panic via pty-req with more than 130 terminal-mode records

Summary A post-authentication denial-of-service panic in russh 0.62.2 commit c4be19f1915c8682f4615c3fd50008512b474491, current default branch main as of 2026-07-22. An authenticated client sends a pty-req channel request carrying more than 130 terminal-mode records. The parser uses a fixed...