Add reactive runtime demos + sx-web federation plan

7 interactive island demos for the reactive runtime layers:
- L0 Ref (timer + DOM handle), L1 Foreign (canvas via host-call),
  L2 Machine (traffic light), L3 Commands (undo/redo),
  L4 Loop (bouncing ball), L5 Keyed Lists, L6 App Shell

Fix OCaml build: add (wrapped false) to lib/dune, remove Sx. qualifiers.
Fix JS build: include dom-lib + browser-lib in adapter compilation.

New plan: sx-web federated component web — browser nodes via WebTransport,
server nodes via IPFS, in-browser authoring, AI composition layer.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

hosts/javascript/bootstrap.py

@@ -130,7 +130,7 @@ def compile_ref_to_js(
         ("render.sx", "render (core)"),
         ("web-forms.sx", "web-forms (defstyle, deftype, defeffect, defrelation)"),
     ]
-    for name in ("parser", "html", "sx", "dom", "engine", "orchestration", "boot"):
+    for name in ("parser", "html", "sx", "dom-lib", "browser-lib", "dom", "engine", "orchestration", "boot"):
         if name in adapter_set:
             sx_files.append(ADAPTER_FILES[name])
     # Use explicit ordering for spec modules (respects dependencies)