chore: sync core lib and CLAUDE.md from agent-core

[avifenesh]

Automated sync of lib/ and CLAUDE.md from agent-core.

---

Note

Low Risk
Low risk utility change limited to truncate, adjusting string length semantics to Unicode code points and adding a guard for maxLength <= 0; potential minor behavior differences for callers relying on UTF-16 length.

Overview
Updates truncate in lib/cross-platform/index.js to truncate by Unicode code points (avoiding broken surrogate pairs like emoji) instead of UTF-16 code units, and to return the input unchanged when maxLength <= 0. Documentation is updated to reflect the new semantics.

^{Reviewed by Cursor Bugbot for commit 7e41029. Configure here.}

[gemini-code-assist]

Warning

You have reached your daily quota limit. Please wait up to 24 hours and I will start processing your requests again!

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit 7e41029. Configure here.}

[cursor]

Negative slice end produces oversized output

Medium Severity

When maxLength is 1 or 2, maxLength - 3 is negative, and Array.prototype.slice treats negative end indices as offsets from the array end (unlike String.prototype.substring, which clamped them to 0). The result keeps almost all of the original code points and appends '...', producing output far longer than maxLength and even longer than the input string.

 

^{Reviewed by Cursor Bugbot for commit 7e41029. Configure here.}