Feature states are visible through the fog of war

If a tree is reclaimed or a wreck created, all players can see this change, even if they have no visibly of that part of the map.

Start by tracing the engine's fog-of-war visibility handling and the code paths that reclaim trees or create wrecks. Determine how those map changes become visible to players, then verify that players without visibility of the affected area no longer see the changes.

Written by the indexing model from the issue text.