SX renderer: adapter-html.sx as sole renderer, conditions, pattern matching

Evaluator: conditions/restarts, pattern matching, render-trace support.
adapter-html.sx: full SX-defined HTML renderer replacing native OCaml.
spec/render.sx: updated render mode helpers.
sx_browser.ml: use SX render-to-html instead of native.
sx_ref.ml: evaluator updates for conditions + match.
Bootstrap + transpiler updates for new forms.

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

hosts/ocaml/lib/sx_primitives.ml

@@ -854,6 +854,10 @@ let () =
     | [Component c] -> c.c_body
     | [Island i] -> i.i_body
     | _ -> Nil);
+  register "component-file" (fun args ->
+    match args with [v] -> component_file v | _ -> Nil);
+  register "component-set-file!" (fun args ->
+    match args with [v; f] -> component_set_file v f | _ -> Nil);
   register "macro?" (fun args ->
     match args with [Macro _] -> Bool true | _ -> Bool false);
   register "for-each-indexed" (fun args ->