React reconciler crash: undefined is not an object (evaluating 'w.length')

Bug Description

Claude Code's terminal UI crashes with a React reconciler error across multiple terminal sessions simultaneously.

Error

ERROR  undefined is not an object (evaluating 'w.length')

 /$bunfs/root/claude:682:20562

The crash originates from React's AH function (stack trace generation) in the minified reconciler code at /$bunfs/root/claude:682.

Environment

• OS: Windows 11 Pro + WSL2 Ubuntu (Linux 6.6.87.2-microsoft-standard-WSL2)
• Claude Code: Latest (installed via npm)
• Runtime: Bun (bundled with Claude Code)
• Terminal: 3 side-by-side terminal sessions all crashed simultaneously

Reproduction

The crash occurred spontaneously across all 3 open Claude Code terminal sessions at the same time. No specific user action triggered it - sessions were idle or mid-conversation.

Additional Context

The full stack trace is minified React/Ink reconciler internals (DH, AH, EH functions), suggesting a rendering issue in the terminal UI layer rather than application logic. The w.length access on undefined appears to be in the fiber stack frame generation code.