trunk
client/components: drop findDOMNode in section-nav; migrate docs-example defaultProps (React 19) (#111622)
Umbrella PR: Calypso Performance Improvements - Take II (#109735)
Remove the signup_url config flag (#103768)
React 19 prep: extract type-safe changes that land under React 18 (#112085)
Remove SCSS prelude feature for better performance - Take II (#111583)