fix: correct feature-report prose, restore update test coverage, warn on sub-0.8.0 upgrades

- generate-complete-framework-report.mjs no longer claims legacyEmit/
  legacyEventProps/legacyComponentDiscovery/stringLayouts/
  functions.legacyDefaultRuntime are usable compatibility flags; they were
  removed before the first public release and a config setting them is now
  rejected. Regenerated docs/WRNEXUS-COMPLETE-FEATURE-REPORT.md.
- Restored the update.test.ts coverage lost in the sub-0.8.0 migration
  cleanup: a 0.8.x fixture now asserts refreshFrameworkFiles' still-live
  behaviour (public/llms.txt and CLAUDE.md creation) and that
  pkg.wrnexus.version stays at its old value after an unverified update.
  The .gitignore refresh and build/start/production script backfill were
  themselves removed as part of dropping the sub-0.8.0 migrations that
  implemented them, so there is nothing left to cover for those two.
- updateApp now logs a clear warning when the detected project version is
  below 0.8.0, naming the version and stating that automated migration from
  below 0.8.0 is no longer supported, without failing the command (a
  marker-less app, like examples/basic-app, is benign and must still
  upgrade cleanly).

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

packages/cli/src/update.ts

@@ -950,6 +950,12 @@ export function updateApp(
   const pkg = JSON.parse(readFileSync(pkgPath, "utf8")) as Record<string, unknown>;
   const from = appVersion(appRoot, pkg);
   const log = (m: string) => console.log(`    ${m}`);
+  if (cmp(from, "0.8.0") < 0) {
+    log(
+      `⚠ detected version ${from}: automated migration from below 0.8.0 is no longer supported. ` +
+        `Only 0.8.x+ migrations will run; review the project manually before relying on this update.`,
+    );
+  }
   const report =
     options.report ??
     ({