fix: address Cubic round-4 P2 issues

- isTodo: allow optional id to match Todo interface, preventing
  todos without ids from being silently dropped
- messageHasContentFromSDK: treat unknown part types as empty
  (continue) instead of content (return true) for parity with
  existing storage logic
- readMessagesFromSDK in recover-empty-content-message-sdk: wrap
  SDK call in try/catch to prevent recovery from throwing

src/hooks/anthropic-context-window-limit-recovery/empty-content-recovery-sdk.ts

@@ -32,7 +32,7 @@ function messageHasContentFromSDK(message: SDKMessage): boolean {
 
     if (TOOL_TYPES.has(type)) return true
 
-    return true
+    continue
   }
 
   return false