JS test harness: 375/469 spec tests pass with full build

- Add --full flag for full-spec build (includes continuations + types)
- Add types module to JS SPEC_MODULES
- 375 tests pass on JavaScript, 94 remaining failures are:
  29 type platform stubs, 14 render format, 6 continuation aliases,
  5 type system platform, 4 string primitive aliases
- Full test build: hosts/javascript/cli.py --extensions continuations
  --spec-modules types --output sx-full-test.js

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

hosts/javascript/run_tests.js

@@ -36,7 +36,15 @@ global.clearTimeout = clearTimeout;
 global.console = console;
 
 // Load the bootstrapped evaluator
-const jsPath = path.join(__dirname, "..", "..", "shared", "static", "scripts", "sx-browser.js");
+// Use --full flag to load a full-spec build (if available)
+const fullBuild = process.argv.includes("--full");
+const jsPath = fullBuild
+  ? path.join(__dirname, "..", "..", "shared", "static", "scripts", "sx-full-test.js")
+  : path.join(__dirname, "..", "..", "shared", "static", "scripts", "sx-browser.js");
+if (fullBuild && !fs.existsSync(jsPath)) {
+  console.error("Full test build not found. Run: python3 hosts/javascript/cli.py --extensions continuations --spec-modules types --output shared/static/scripts/sx-full-test.js");
+  process.exit(1);
+}
 const Sx = require(jsPath);
 if (!Sx || !Sx.parse) {
   console.error("Failed to load Sx evaluator");
@@ -95,6 +103,16 @@ env["make-continuation"] = function(fn) {
 env["continuation?"] = function(x) { return x != null && x._continuation === true; };
 env["continuation-fn"] = function(c) { return c.fn; };
 
+// Render helpers
+if (Sx.renderToHtml) {
+  env["render-html"] = function(expr, e) { return Sx.renderToHtml(expr, e || env); };
+}
+
+// Type system helpers — available when types module is included
+env["test-prim-param-types"] = function(name, types) { return null; };
+env["component-param-types"] = function(c) { return c && c._paramTypes ? c._paramTypes : null; };
+env["component-set-param-types!"] = function(c, t) { if (c) c._paramTypes = t; return null; };
+
 // Platform test functions
 env["try-call"] = function(thunk) {
   try {
@@ -142,7 +160,7 @@ for (const expr of frameworkExprs) {
 }
 
 // Determine which tests to run
-const args = process.argv.slice(2);
+const args = process.argv.slice(2).filter(a => !a.startsWith("--"));
 let testFiles = [];
 
 if (args.length > 0) {