test: 20 security tests for audit remediation

- server-auth: verify token removed from /health, auth on /refs, /activity/*
- cookie-picker: auth required on data routes, HTML page unauthenticated
- path-validation: symlink bypass blocked, realpathSync failure throws
- gstack-config: regex key rejected, sed special chars preserved
- state-ttl: savedAt timestamp, 7-day TTL warning
- telemetry: branch/repo with quotes don't corrupt JSON
- adversarial: sidepanel escapes entry.command, freeze prefix collision

browse/test/adversarial-security.test.ts

@@ -0,0 +1,32 @@
+/**
+ * Adversarial security tests — XSS and boundary-check hardening
+ *
+ * Test 19: Sidepanel escapes entry.command in activity feed (prevents XSS)
+ * Test 20: Freeze hook uses trailing slash in boundary check (prevents prefix collision)
+ */
+
+import { describe, test, expect } from 'bun:test';
+import * as fs from 'fs';
+import * as path from 'path';
+
+describe('Adversarial security', () => {
+  test('sidepanel escapes entry.command in activity feed', () => {
+    const source = fs.readFileSync(
+      path.join(import.meta.dir, '../../extension/sidepanel.js'),
+      'utf-8',
+    );
+    // entry.command must be wrapped in escapeHtml() to prevent XSS injection
+    // via crafted command names in the activity feed
+    expect(source).toContain('escapeHtml(entry.command');
+  });
+
+  test('freeze hook uses trailing slash in boundary check', () => {
+    const source = fs.readFileSync(
+      path.join(import.meta.dir, '../../freeze/bin/check-freeze.sh'),
+      'utf-8',
+    );
+    // The boundary check must use "${FREEZE_DIR}/" with a trailing slash
+    // to prevent prefix collision (e.g., /app matching /application)
+    expect(source).toContain('"${FREEZE_DIR}/"');
+  });
+});