[Bug] Rust panic: Invalid UTF-8 byte boundary in string processing

Bug Description
On v2.0.70, I encountered the following bug:

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thread '<unnamed>' (633517) panicked at /rustc/ed61e7d7e242494fb7057f2657300d9e77bb4fcb/library/core/src/str/mod.rs:833:21:
byte index 17 is not a char boundary; it is inside 'る' (bytes 15..18) of `習熟している** | 技術的リスクが低い |`
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
fatal runtime error: failed to initiate panic, error 5, aborting
Abort trap: 6
macbook-akira:my-repo akira$ 

I'm getting an error stating that rust has panicked. Is this due to my environment, or has the behavior changed somehow after the version upgrade? My macOS is v15.7.2, and I installed Claude Code using the following command:

curl -fsSL https://claude.ai/install.sh | bash

Environment Info

• Platform: darwin
• Terminal: Apple_Terminal
• Version: 2.0.70
• Feedback ID: 7d57c866-2ddb-4401-a95f-9a4c248eada6

Errors

[{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/akira/.local/share/claude/versions/2.0.70 (expected in multi-process scenarios)\n    at K$R (/$bunfs/root/claude:2346:2155)\n    at qDA (/$bunfs/root/claude:2346:1875)\n    at processTicksAndRejections (native:7:39)","timestamp":"2025-12-16T04:59:32.788Z"}]