feat: add workflow snapshot codec registry and strict sanitization

src/app_runtime/workflow/persistence/codec_registry.py

@@ -0,0 +1,24 @@
+from __future__ import annotations
+
+from typing import Any
+
+from app_runtime.workflow.persistence.entity_codec import EntityCodec
+
+
+class CodecRegistry:
+    def __init__(self, codecs: list[EntityCodec] | None = None) -> None:
+        self._codecs = list(codecs or [])
+        self._by_type_id = {codec.type_id: codec for codec in self._codecs}
+
+    def register(self, codec: EntityCodec) -> None:
+        self._codecs.append(codec)
+        self._by_type_id[codec.type_id] = codec
+
+    def find_for_value(self, value: Any) -> EntityCodec | None:
+        for codec in self._codecs:
+            if codec.can_encode(value):
+                return codec
+        return None
+
+    def find_by_type_id(self, type_id: str) -> EntityCodec | None:
+        return self._by_type_id.get(type_id)