feat: add live replays and PostgreSQL maintenance tools

- Stream compact live replay updates across local and clustered dashboards.
- Render responsive snake bodies as SVG paths with aligned custom icons.
- Add cache-busted assets, replay fallback routes, and live-follow playback.
- Support PostgreSQL benchmark sampling and idempotent SQLite migration.
- Add dry-run cleanup for old low-quality PostgreSQL replay payloads.
- Reward safe perimeter lanes and bump Prism to version 1.5.0.
- Add backend, migration, dashboard, and perimeter regression coverage.

tests/test_BenchmarkStates.py

@@ -0,0 +1,30 @@
+import unittest
+
+from server.database.benchmark_states import _build_state, is_postgresql_source
+
+class TestBenchmarkStates(unittest.TestCase):
+  def test_detects_postgresql_dsn(self):
+    self.assertTrue(is_postgresql_source("postgresql://user:pass@example.com/db"))
+    self.assertTrue(is_postgresql_source("postgres://user:pass@example.com/db"))
+    self.assertFalse(is_postgresql_source("/tmp/gameplay.sqlite3"))
+
+  def test_builds_normalized_state_from_postgresql_json_values(self):
+    row = (
+      1, {}, {}, [{"x": 5, "y": 5}], [], "you-id", "You", 11, 11,
+      "game-id", "league", "standard", "standard", "v1", 7,
+    )
+    snake_rows = [
+      ("you-id", "You", 90, 3, 1, 2, [{"x": 1, "y": 2}], {"head": "default"}),
+    ]
+
+    state = _build_state(row, snake_rows)
+
+    self.assertIsNotNone(state)
+    board, metadata = state
+    self.assertEqual(board["food"], [{"x": 5, "y": 5}])
+    self.assertEqual(board["snakes"][0]["id"], "you-id")
+    self.assertEqual(metadata["you"]["id"], "you-id")
+    self.assertEqual(metadata["turn"], 7)
+
+if __name__ == "__main__":
+  unittest.main()