[Bug] Extended thinking disabled by default in new sessions

Bug Description
claude code sets thinking off by default on every new chat. previously it always on

Environment Info

• Platform: darwin
• Terminal: Apple_Terminal
• Version: 2.0.62
• Feedback ID: 7d09ea1f-ad77-4a42-9ac8-593334a2f66b

Errors

[{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/irumi/.local/share/claude/versions/2.0.64 (expected in multi-process scenarios)\n    at zh0 (/$bunfs/root/claude:2728:1620)\n    at sCA (/$bunfs/root/claude:2726:35591)\n    at async TJA (/$bunfs/root/claude:2728:3431)\n    at processTicksAndRejections (native:7:39)","timestamp":"2025-12-10T14:22:20.588Z"},{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/irumi/.local/share/claude/versions/2.0.62 (expected in multi-process scenarios)\n    at zh0 (/$bunfs/root/claude:2728:1620)\n    at RJA (/$bunfs/root/claude:2728:1298)\n    at processTicksAndRejections (native:7:39)","timestamp":"2025-12-10T14:22:20.589Z"},{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/irumi/.local/share/claude/versions/2.0.64 (expected in multi-process scenarios)\n    at zh0 (/$bunfs/root/claude:2728:1620)\n    at sCA (/$bunfs/root/claude:2726:35591)\n    at async V$7 (/$bunfs/root/claude:2726:37692)\n    at async Ag (/$bunfs/root/claude:2728:236)\n    at async <anonymous> (/$bunfs/root/claude:2728:13013)\n    at processTicksAndRejections (native:7:39)","timestamp":"2025-12-10T14:22:29.081Z"}]