fix: correct wallmood parameter name to wall_message_id (v0.4.3)

API error message confirmed the expected parameter is 'wall_message_id',
not 'wallId'. SPEC.md updated to reflect verified finding.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/mcp_familywall/server.py

@@ -490,9 +490,11 @@ def like_post(post_id: str, like: bool = True) -> str:
     # wallmood is a toggle endpoint — same endpoint for like and unlike.
     # The 'like' parameter controls the intended state; since the endpoint
     # toggles server-side state, it is sent as 'moodType' to allow the server
-    # to differentiate. Exact parameter names to be verified via FW_DEBUG=1.
+    # to differentiate.
+    # Verified: correct parameter name is 'wall_message_id' (API error message confirmed).
+    # 'moodType' values ("LIKE" / "NONE") still to be confirmed via FW_DEBUG=1.
     params: dict[str, Any] = {
-        "wallId": post_id,
+        "wall_message_id": post_id,
         "moodType": "LIKE" if like else "NONE",
     }