test: add relay ping rate-limit coverage + limiter LRU eviction

tests/test_atlas_rate_limit.py

@@ -49,6 +49,20 @@ def test_bounded_rate_limiter_ttl_cleanup_and_limit():
     assert "k1" not in limiter._entries
 
 
+def test_bounded_rate_limiter_enforces_max_entries_lru_eviction():
+    limiter = beacon_chat.BoundedRateLimiter(max_entries=2, ttl_seconds=999, cleanup_interval_seconds=1)
+
+    assert limiter.allow("k1", 5, now=100)
+    assert limiter.allow("k2", 5, now=100)
+
+    # Trigger cleanup cycle and insert a third key to force LRU eviction.
+    assert limiter.allow("k3", 5, now=101)
+
+    assert "k1" not in limiter._entries
+    assert "k2" in limiter._entries
+    assert "k3" in limiter._entries
+
+
 def test_api_bounties_read_rate_limit():
     beacon_chat.app.config["TESTING"] = True
     beacon_chat.app.config["RATE_LIMIT_READ_PER_MIN"] = 1
@@ -71,3 +85,21 @@ def test_write_rate_limit_on_chat_endpoint():
 
     assert r1.status_code == 400
     assert r2.status_code == 429
+
+
+def test_write_rate_limit_on_relay_ping_endpoint():
+    beacon_chat.app.config["TESTING"] = True
+    beacon_chat.app.config["RATE_LIMIT_WRITE_PER_MIN"] = 1
+
+    client = beacon_chat.app.test_client()
+    payload = {
+        "agent_id": "bcn_unsigned_rate_limit",
+        "name": "Unsigned",
+        "pubkey_hex": "00" * 32,
+    }
+
+    r1 = client.post("/relay/ping", json=payload, environ_overrides={"REMOTE_ADDR": "10.3.3.3"})
+    r2 = client.post("/relay/ping", json=payload, environ_overrides={"REMOTE_ADDR": "10.3.3.3"})
+
+    assert r1.status_code == 400
+    assert r2.status_code == 429