158: Fix CodeEditor auto-save triggering on every keystroke

[lattln]

Summary

Fixes a bug where the Monaco CodeEditor auto-saved on every keystroke, causing partially typed (invalid) YAML/JSON to be parsed and normalized prematurely. This resulted in cursor jumps, duplicated fields, and lost input while typing.

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Root Cause

A cleanup effect in CodeEditor.jsx depended on values that changed on each keystroke. When validation updated UI state, the effect re-ran, triggering the cleanup logic and unintentionally saving partial code.

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Fix

• Moved cleanup logic to run only on unmount
• Stored mutable dependencies (replaceAll, ui, definition, format) in useRef
• Updated refs on change, but read from refs during cleanup
• Eliminated keystroke-triggered cleanup while preserving validation

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Result

• Typing no longer triggers auto-save
• Invalid / partial YAML or JSON is allowed while editing
• Auto-save occurs only when switching away from the editor
• Live validation still surfaces syntax errors in the UI

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Files Changed

• CodeEditor.jsx