Fix aser server-affinity expansion: keyword values, OOB wrapper, page helpers

Three bugs in aser-expand-component (adapter-sx.sx):
- Keyword values were eval'd (eval-expr can't handle <>, HTML tags);
  now asered, matching the aser's rendering capabilities
- Missing default nil binding for unset &key params (caused
  "Undefined symbol" errors for optional params like header-rows)
- aserCall string-quoted keyword values that were already serialized
  SX — now inlines values starting with "(" directly

Server-affinity annotations for layout/nav shells:
- ~shared:layout/app-body, ~shared:layout/oob-sx — page structure
- ~layouts/nav-sibling-row, ~layouts/nav-children — server-side data
- ~layouts/doc already had :affinity :server
- ~cssx/flush marked :affinity :client (browser-only state)

Navigation fix: restore oob_page_sx wrapper for HTMX responses
so #main-panel section exists for sx-select/sx-swap targeting.

OCaml bridge: lazy page helper injection into kernel via IO proxy
(define name (fn (...) (helper "name" ...))) — enables aser_slot
to evaluate highlight/component-source etc. via coroutine bridge.

Playwright tests: added pageerror listener to test_no_console_errors,
new test_navigate_from_home_to_geography for HTMX nav regression.

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

shared/sx/helpers.py

@@ -364,10 +364,6 @@ async def _render_to_sx_with_env(__name: str, extra_env: dict, **kwargs: Any) ->
     """
     from .jinja_bridge import get_component_env, _get_request_context
     import os
-    if os.environ.get("SX_USE_REF") == "1":
-        from .ref.async_eval_ref import async_eval_slot_to_sx
-    else:
-        from .async_eval import async_eval_slot_to_sx
     from .types import Symbol, Keyword, NIL as _NIL
 
     # Build AST with extra_env entries as keyword args so _aser_component
@@ -381,6 +377,19 @@ async def _render_to_sx_with_env(__name: str, extra_env: dict, **kwargs: Any) ->
         ast.append(Keyword(k.replace("_", "-")))
         ast.append(v if v is not None else _NIL)
 
+    if os.environ.get("SX_USE_OCAML") == "1":
+        from .ocaml_bridge import get_bridge
+        from .parser import serialize
+        bridge = await get_bridge()
+        sx_text = serialize(ast)
+        ocaml_ctx = {"_helper_service": _get_request_context().get("_helper_service", "")} if isinstance(_get_request_context(), dict) else {}
+        return SxExpr(await bridge.aser_slot(sx_text, ctx=ocaml_ctx))
+
+    if os.environ.get("SX_USE_REF") == "1":
+        from .ref.async_eval_ref import async_eval_slot_to_sx
+    else:
+        from .async_eval import async_eval_slot_to_sx
+
     env = dict(get_component_env())
     env.update(extra_env)
     ctx = _get_request_context()
@@ -399,12 +408,21 @@ async def _render_to_sx(__name: str, **kwargs: Any) -> str:
     """
     from .jinja_bridge import get_component_env, _get_request_context
     import os
+
+    ast = _build_component_ast(__name, **kwargs)
+
+    if os.environ.get("SX_USE_OCAML") == "1":
+        from .ocaml_bridge import get_bridge
+        from .parser import serialize
+        bridge = await get_bridge()
+        sx_text = serialize(ast)
+        return SxExpr(await bridge.aser(sx_text))
+
     if os.environ.get("SX_USE_REF") == "1":
         from .ref.async_eval_ref import async_eval_to_sx
     else:
         from .async_eval import async_eval_to_sx
 
-    ast = _build_component_ast(__name, **kwargs)
     env = dict(get_component_env())
     ctx = _get_request_context()
     return SxExpr(await async_eval_to_sx(ast, env, ctx))
@@ -420,6 +438,10 @@ async def render_to_html(__name: str, **kwargs: Any) -> str:
 
     Same as render_to_sx() but produces HTML output instead of SX wire
     format. Used by route renders that need HTML (full pages, fragments).
+
+    Note: does NOT use OCaml bridge — the shell render is a pure HTML
+    template with no IO, so the Python renderer handles it reliably.
+    The OCaml path is used for _render_to_sx and _eval_slot (IO-heavy).
     """
     from .jinja_bridge import get_component_env, _get_request_context
     import os