[Clemens Koprolin (clemenskoprolin)]

This PR adds form-state serialization to Compose HTML EAP string rendering. Input values and checked state are written as HTML attributes, while textarea values and defaults are written as escaped text content.

Controlled state takes precedence over defaults. Hydration recognizes serialized textarea content and applies controlled client state without reporting hydration mismatches with default attributes.

Also fixes the EAP textarea default setter to use the native defaultValue property instead of innerText, preserving line breaks and user edits when defaults change.

Solves CMP-10774.

Testing

Run from the html directory:

./gradlew -Pcompose.html.eap.enabled=true \
  :html-core-eap:jvmTest \
  :html-core-eap:jsBrowserTest \
  :html-core-eap:wasmJsBrowserTest

Release Notes

N/A