feat(hot-reload): Add HotModule dataclass and HotReloader registry

src/hot_reloader.py

@@ -0,0 +1,32 @@
+from __future__ import annotations
+from dataclasses import dataclass, field
+from typing import Any
+import copy
+import traceback
+
+@dataclass
+class HotModule:
+    name: str
+    file_path: str
+    state_keys: list[str] = field(default_factory=list)
+    delegation_targets: list[str] = field(default_factory=list)
+
+class HotReloader:
+    HOT_MODULES: dict[str, HotModule] = {}
+    last_error: str | None = None
+    is_error_state: bool = False
+
+    @classmethod
+    def register(cls, module: HotModule) -> None:
+        if module.name in cls.HOT_MODULES:
+            raise ValueError(f"Module {module.name} already registered")
+        cls.HOT_MODULES[module.name] = module
+
+    @classmethod
+    def capture_state(cls, app: Any, state_keys: list[str]) -> dict[str, Any]:
+        return {key: copy.deepcopy(getattr(app, key, None)) for key in state_keys if hasattr(app, key)}
+
+    @classmethod
+    def restore_state(cls, app: Any, state: dict[str, Any]) -> None:
+        for key, value in state.items():
+            setattr(app, key, value)