Bootstrap CEK as default evaluator on both JS and Python sides

SPEC_MODULES + SPEC_MODULE_ORDER for frames/cek in platform_js.py,
PLATFORM_CEK_JS + CEK_FIXUPS_JS constants, auto-inclusion in
run_js_sx.py, 70+ RENAMES in js.sx. Python: CEK always-include in
bootstrap_py.py, eval_expr/trampoline overridden to cek_run in
platform_py.py with _tree_walk_* preserved for test runners.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

shared/sx/ref/bootstrap_py.py

@@ -1122,6 +1122,7 @@ try:
     from .platform_py import (
         PREAMBLE, PLATFORM_PY, PRIMITIVES_PY_PRE, PRIMITIVES_PY_POST,
         PRIMITIVES_PY_MODULES, _ALL_PY_MODULES,
+        PLATFORM_PARSER_PY,
         PLATFORM_DEPS_PY, PLATFORM_CEK_PY, CEK_FIXUPS_PY, PLATFORM_ASYNC_PY,
         FIXUPS_PY, CONTINUATIONS_PY,
         _assemble_primitives_py, public_api_py,
@@ -1132,6 +1133,7 @@ except ImportError:
     from shared.sx.ref.platform_py import (
         PREAMBLE, PLATFORM_PY, PRIMITIVES_PY_PRE, PRIMITIVES_PY_POST,
         PRIMITIVES_PY_MODULES, _ALL_PY_MODULES,
+        PLATFORM_PARSER_PY,
         PLATFORM_DEPS_PY, PLATFORM_CEK_PY, CEK_FIXUPS_PY, PLATFORM_ASYNC_PY,
         FIXUPS_PY, CONTINUATIONS_PY,
         _assemble_primitives_py, public_api_py,
@@ -1224,7 +1226,7 @@ def compile_ref_to_py(
 
     Args:
         adapters: List of adapter names to include.
-                  Valid names: html, sx.
+                  Valid names: parser, html, sx.
                   None = include all server-side adapters.
         modules: List of primitive module names to include.
                  core.* are always included. stdlib.* are opt-in.
@@ -1277,9 +1279,9 @@ def compile_ref_to_py(
             spec_mod_set.add("page-helpers")
         if "router" in SPEC_MODULES:
             spec_mod_set.add("router")
-    # cek module requires frames
-    if "cek" in spec_mod_set:
-        spec_mod_set.add("frames")
+    # CEK is the canonical evaluator — always include
+    spec_mod_set.add("cek")
+    spec_mod_set.add("frames")
     has_deps = "deps" in spec_mod_set
     has_cek = "cek" in spec_mod_set
 
@@ -1289,6 +1291,9 @@ def compile_ref_to_py(
         ("forms.sx", "forms (server definition forms)"),
         ("render.sx", "render (core)"),
     ]
+    # Parser before html/sx — provides serialize used by adapters
+    if "parser" in adapter_set:
+        sx_files.append(ADAPTER_FILES["parser"])
     for name in ("html", "sx"):
         if name in adapter_set:
             sx_files.append(ADAPTER_FILES[name])
@@ -1348,6 +1353,7 @@ def compile_ref_to_py(
     # Build output
     has_html = "html" in adapter_set
     has_sx = "sx" in adapter_set
+    has_parser = "parser" in adapter_set
 
     parts = []
     parts.append(PREAMBLE)
@@ -1356,6 +1362,9 @@ def compile_ref_to_py(
     parts.append(_assemble_primitives_py(prim_modules))
     parts.append(PRIMITIVES_PY_POST)
 
+    if has_parser:
+        parts.append(PLATFORM_PARSER_PY)
+
     if has_deps:
         parts.append(PLATFORM_DEPS_PY)