Chisle review

Review the diff/file for what could be deleted or simplified, not for style nits.

What to flag

• Abstraction with one implementation (interface/factory/wrapper for a single case)
• Reinvented stdlib (hand-rolled debounce, deep-clone, groupBy, date math)
• New dependency for what a few lines or an installed dep already does
• Config/option that never varies
• Speculative "for later" scaffolding with no current caller
• Verbose code where a native platform feature (CSS, DB constraint, <input type>) does it

What NOT to flag

• Input validation at trust boundaries
• Error handling that prevents data loss
• Security / accessibility code
• Anything the task explicitly required