feat(kevin_bridge): exit-scan daily job + cursor + audit writer

tests/services/kevin_signal_bridge/test_cursor.py

@@ -0,0 +1,27 @@
+"""Tests for the Redis cursor."""
+
+import fakeredis.aioredis
+
+from services.kevin_signal_bridge.cursor import RedisCursor
+
+
+async def _redis():
+    return fakeredis.aioredis.FakeRedis()
+
+
+async def test_cursor_defaults_to_zero():
+    cursor = RedisCursor(await _redis())
+    assert await cursor.last_seen_id() == 0
+
+
+async def test_cursor_advance_persists_value():
+    cursor = RedisCursor(await _redis())
+    await cursor.advance(42)
+    assert await cursor.last_seen_id() == 42
+
+
+async def test_cursor_advance_never_goes_backwards():
+    cursor = RedisCursor(await _redis())
+    await cursor.advance(42)
+    await cursor.advance(10)
+    assert await cursor.last_seen_id() == 42