feat: add Zenith strategy and move latency tracing

- Register Zenith 1.1 with balanced duel verdicts and forced-outcome overrides.
- Prioritize permanent-trail space in Constrictor and health-aware hazard routes.
- Deduct executor queue delays and return fallback directions on move timeouts.
- Correlate response headers, replay timings, and sampled structured trace logs.
- Move shared metrics publication off the response path without losing local counts.
- Allow configurable tournament opponents and add a psql helper recipe.
- Preserve empty latency values through compact replay encoding and migration.
- Update Arena game links and use default assets for missing customizations.
- Cover strategy, HTTP lifecycle, tracing, replay codecs, and dashboard behavior.
- Validate with 260 passing Python tests, 4 skips, and 2 passing JavaScript tests.

tests/test_CompactStorage.py

@@ -42,7 +42,8 @@ class TestCodec(unittest.TestCase):
     for move in ("up", "down", "left", "right", None):
       self.assertEqual(decode_move(encode_move(move)), move)
     self.assertEqual(decode_latency(encode_latency("77")), "77")
-    self.assertIsNone(encode_latency(""))
+    self.assertEqual(decode_latency(encode_latency("")), "")
+    self.assertIsNone(decode_latency(encode_latency(None)))
     self.assertIsNone(encode_latency("timeout"))
 
   def test_epoch_microseconds_roundtrip(self):