Add a canvas leaf-widget island to the techdemo that receives server snapshots through Effect::event/CustomEvent while keeping slhx core and runtime semantics unchanged.
req: interop/001
req: examples/001
req: examples/005
Move the techdemo page shell and remaining board/inspector/hero boundaries to hemplate-owned views instead of Rust raw HTML or placeholder replacement. Keep rendered HTML assertions DOM-aware with scraper.
req: html_safety/002
req: view/001
req: test/005
slhx agent