Add 5 MCP tools, refactor nav-data, fix deep path bug, fix Playwright failures

Nav refactoring:
- Split nav-data.sx (32 forms) into 6 files: nav-geography, nav-language,
  nav-applications, nav-etc, nav-tools, nav-tree
- Add Tools top-level nav category with SX Tools and Services pages
- New services-tools.sx page documenting the rose-ash-services MCP server

JS build fixes (fixes 5 Playwright failures):
- Wire web/web-signals.sx into JS build (stores, events, resources)
- Add cek-try primitive to JS platform (island hydration error handling)
- Merge PRIMITIVES into getRenderEnv (island env was missing primitives)
- Rename web/signals.sx → web/web-signals.sx to avoid spec/ collision

New MCP tools:
- sx_trace: step-through CEK evaluation showing lookups, calls, returns
- sx_deps: dependency analysis — free symbols + cross-file resolution
- sx_build_manifest: show build contents for JS and OCaml targets
- sx_harness_eval extended: multi-file loading + setup expressions

Deep path bug fix:
- Native OCaml list-replace and navigate bypass CEK callback chain
- Fixes sx_replace_node and sx_read_subtree corruption on paths 6+ deep

Tests: 1478/1478 JS full suite, 91/91 Playwright

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

hosts/javascript/platform.py

@@ -61,6 +61,7 @@ SPEC_MODULES = {
     "deps": ("deps.sx", "deps (component dependency analysis)"),
     "router": ("router.sx", "router (client-side route matching)"),
     "signals": ("signals.sx", "signals (reactive signal runtime)"),
+    "signals-web": ("web-signals.sx", "signals-web (stores, events, resources)"),
     "page-helpers": ("page-helpers.sx", "page-helpers (pure data transformation helpers)"),
     "types": ("types.sx", "types (gradual type system)"),
     "vm": ("vm.sx", "vm (bytecode virtual machine)"),
@@ -68,7 +69,7 @@ SPEC_MODULES = {
 # Note: frames and cek are now part of evaluator.sx (always loaded as core)
 
 # Explicit ordering for spec modules with dependencies.
-SPEC_MODULE_ORDER = ["deps", "page-helpers", "router", "signals", "types", "vm"]
+SPEC_MODULE_ORDER = ["deps", "page-helpers", "router", "signals", "signals-web", "types", "vm"]
 
 
 EXTENSION_NAMES = {"continuations"}
@@ -2665,6 +2666,17 @@ PLATFORM_ORCHESTRATION_JS = """
       : catchFn;
     try { return t(); } catch (e) { return c(e); }
   }
+  function cekTry(thunkFn, handlerFn) {
+    try {
+      var result = _wrapSxFn(thunkFn)();
+      if (!handlerFn || handlerFn === NIL) return [SYM("ok"), result];
+      return result;
+    } catch (e) {
+      var msg = (e && e.message) ? e.message : String(e);
+      if (handlerFn && handlerFn !== NIL) return _wrapSxFn(handlerFn)(msg);
+      return [SYM("error"), msg];
+    }
+  }
   function errorMessage(e) {
     return e && e.message ? e.message : String(e);
   }
@@ -3077,7 +3089,7 @@ PLATFORM_BOOT_JS = """
   }
 
   function getRenderEnv(extraEnv) {
-    return extraEnv ? merge(componentEnv, extraEnv) : componentEnv;
+    return extraEnv ? merge(componentEnv, PRIMITIVES, extraEnv) : merge(componentEnv, PRIMITIVES);
   }
 
   function mergeEnvs(base, newEnv) {
@@ -3287,7 +3299,18 @@ def fixups_js(has_html, has_sx, has_dom, has_signals=False, has_deps=False, has_
     try { localStorage.removeItem(key); } catch (e) {}
     return NIL;
   };
-  if (typeof sxParse === "function") PRIMITIVES["sx-parse"] = sxParse;''']
+  if (typeof sxParse === "function") PRIMITIVES["sx-parse"] = sxParse;
+  PRIMITIVES["cek-try"] = function(thunkFn, handlerFn) {
+    try {
+      var result = _wrapSxFn(thunkFn)();
+      if (!handlerFn || handlerFn === NIL) return [SYM("ok"), result];
+      return result;
+    } catch (e) {
+      var msg = (e && e.message) ? e.message : String(e);
+      if (handlerFn && handlerFn !== NIL) return _wrapSxFn(handlerFn)(msg);
+      return [SYM("error"), msg];
+    }
+  };''']
     if has_deps:
         lines.append('''
   // Platform deps functions (native JS, not transpiled — need explicit registration)