Add final Patrol browser compatibility entrypoint

Define the desktop and narrow-screen entrypoint for native abort compatibility and strict scoped reversal checks. The shared harness and fixture bridge are completed in the following commit.

Contract-Neutral: Offline browser verification entrypoint only; no runtime or subsystem semantics change.
Change-source: pulse-maintainer

frontend-modern/browser-tests/patrol-rule-removal-compatibility.cjs

@@ -0,0 +1,29 @@
+// Final shared-client content: native abort compatibility and production
+// one-attempt reversal controls in desktop Chromium and narrow WebKit.
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+const { journey, report, output } = require('/workspace/frontend-modern/browser-tests/patrol-rule-removal.cjs');
+(async () => {
+  try {
+    await journey('/workspace/frontend-modern', 'chromium', 1365, false, true, false, true);
+    await journey('/workspace/frontend-modern', 'webkit', 320, false, true, false, true);
+    assert.equal(report.cases.length, 2);
+    assert(report.cases.every((c) => c.abortCompatibility && c.checks.length === 5));
+    report.result = 'passed';
+  } catch (error) {
+    report.result = 'failed';
+    report.failure = error.message;
+    throw error;
+  } finally {
+    report.cleanup = {
+      all_cases_closed: report.cases.every((c) => c.cleanup.browser_closed && c.cleanup.server_closed),
+    };
+    fs.writeFileSync(path.join(output, 'compatibility-result.json'), JSON.stringify(report, null, 2));
+  }
+  console.log(JSON.stringify({ result: report.result, cases: report.cases.length,
+    captures: report.captures.length, cleanup: report.cleanup }));
+})().catch((error) => {
+  console.error(error.stack);
+  process.exitCode = 1;
+});