Generate makeProps and wrapper make for native mode

The new server-reason-react PPX (68070f3e) transforms uppercase JSX
calls from Component.make(~prop, ()) to
Component.make(Component.makeProps(~prop, ())).

styled-ppx's native module generation didn't produce a makeProps
function, causing 'Unbound value Cositas.makeProps' errors.

Fix: for native mode, generate makeProps as a function that captures
all labeled props into a closure (thunk) and a public make wrapper
that invokes the thunk with ?key. The include struct...end pattern
shadows the internal make with the public wrapper.

Also fix the demo server.re to call CSS.style_tag() directly since
it's a plain function, not a React component module.

Author: davesnx

.cursor/hooks/state/continual-learning.json

@@ -0,0 +1,8 @@
+{
+  "version": 1,
+  "lastRunAtMs": 0,
+  "turnsSinceLastRun": 5,
+  "lastTranscriptMtimeMs": null,
+  "lastProcessedGenerationId": "5c59e9fa-8cd2-4751-9b74-b062db9c2e6b",
+  "trialStartedAtMs": null
+}

.opencode/package-lock.json

@@ -2,4 +2,4 @@ print_endline("\n\n");
 print_endline(ReactDOM.renderToStaticMarkup(<App />));
 
 print_endline("\nStyle tag:");
-print_endline(ReactDOM.renderToStaticMarkup(<CSS.style_tag />));
+print_endline(ReactDOM.renderToStaticMarkup(CSS.style_tag()));