chore(changeset): adding a change set

Author: MaxwellCohen

.changeset/swift-owls-stream.md

@@ -0,0 +1,7 @@
+---
+"preact-render-to-string": minor
+---
+
+Stream deferred content using DPU `<template for>` patches and a MutationObserver client script instead of `<preact-island>` custom elements.
+
+Fallbacks are wrapped with processing-instruction markers, and SVG/MathML subtrees are re-parsed so they display correctly after replacement. Streaming is still alpha, so this wire-format change is a minor.