test: add overlay debounce tests

tests/test_crisis_overlay_focus_trap.py

@@ -53,5 +53,36 @@ class TestCrisisOverlayFocusTrap(unittest.TestCase):
         )
 
 
+    def test_overlay_debounce_rate_limiting(self):
+        """Crisis overlay has 10-minute debounce to prevent spam."""
+        self.assertRegex(
+            self.html,
+            r"_lastOverlayShownTime",
+            'Expected overlay debounce timestamp variable.',
+        )
+        self.assertRegex(
+            self.html,
+            r"OVERLAY_DEBOUNCE_MS\s*=\s*10\s*\*\s*60\s*\*\s*1000",
+            'Expected 10-minute debounce window (600000ms).',
+        )
+        self.assertRegex(
+            self.html,
+            r"Date\.now\(\)\s*-\s*_lastOverlayShownTime.*OVERLAY_DEBOUNCE_MS",
+            'Expected showOverlay to check time since last shown.',
+        )
+
+    def test_overlay_force_bypasses_debounce(self):
+        """showOverlay(force) bypasses rate limiting for manual access."""
+        self.assertRegex(
+            self.html,
+            r"function\s+showOverlay\s*\(\s*force\s*\)",
+            'Expected showOverlay to accept force parameter.',
+        )
+        self.assertRegex(
+            self.html,
+            r"!force\s*&&",
+            'Expected force flag to bypass debounce check.',
+        )
+
 if __name__ == '__main__':
     unittest.main()