MarkdownEditor's plugins useMemo depended on imageUploadHandler, which
was a new arrow function on every parent render. This caused MDXEditor
to reinitialize plugins on each render, firing onChange, which updated
the overlay state in AgentConfigForm, triggering a parent re-render —
creating an infinite "Maximum update depth exceeded" loop.
Fix: use a stable ref for imageUploadHandler so plugins are only created
once (keyed on whether a handler exists, not its identity). Also use a
module-level empty object for env config fallback to avoid unnecessary
EnvVarEditor re-renders.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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