- Created src/cleveragents/acms/storage/__init__.py - new storage subpackage
- Created src/cleveragents/acms/storage/hot.py - HotStorageTier class backed by
  OrderedDict for O(1) LRU operations with configurable max_entries and max_bytes
  capacity parameters, optional on_evict callback for warm-tier demotion,
  hit_count/miss_count/entry_count/size_bytes metrics, and threading.RLock safety
- Updated src/cleveragents/acms/__init__.py to export HotStorageTier
- Created features/acms_hot_storage_tier.feature with 36 BDD scenarios covering
  construction, put/get, LRU eviction, eviction callbacks, remove, clear, and
  thread safety
- Created features/steps/acms_hot_storage_tier_steps.py with step definitions
- All quality gates pass: lint, typecheck, unit_tests (36/36 scenarios)

ISSUES CLOSED: #9972

@@ -0,0 +125,4 @@
+
+
+@then('removing "{entry_id}" from the hot tier should return "{expected}"')
+def step_then_remove_returns(context: Any, entry_id: str, expected: str) -> None:

@@ -0,0 +136,4 @@
+    assert result is None, f"Expected None, got {result!r}"
+
+
+# ---------------------------------------------------------------------------