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_MoveTrace.py

@@ -0,0 +1,29 @@
+import unittest
+from unittest.mock import Mock, patch
+from server.services.move_trace import MoveTrace
+
+class TestMoveTrace(unittest.TestCase):
+  def test_snapshot_is_independent_and_stage_survives_exception(self):
+    trace = MoveTrace('test-game', 1)
+    with self.assertRaises(ValueError):
+      with trace.stage('test'):
+        raise ValueError()
+    snapshot = trace.snapshot()
+    snapshot['test_ms'] = -1
+    self.assertGreaterEqual(trace.snapshot()['test_ms'], 0)
+
+  def test_timeout_logged_even_when_sampling_disabled(self):
+    trace = MoveTrace('test-game', 2)
+    trace.set(timed_out=True)
+    logger = Mock()
+    with patch.dict('os.environ', {'MOVE_TRACE_SAMPLE_EVERY':'0'}):
+      trace.log(logger)
+    logger.info.assert_called_once()
+    self.assertIn(trace.id, logger.info.call_args.args[1])
+
+  def test_fast_requests_not_logged_when_disabled(self):
+    trace = MoveTrace('test-game', 2)
+    logger = Mock()
+    with patch.dict('os.environ', {'MOVE_TRACE_SAMPLE_EVERY':'0'}):
+      trace.log(logger)
+    logger.info.assert_not_called()