don't re-export StaticSim from sim/mod.rs

this way we can clearly spot the legacy users.

crates/post/src/lib.rs

@@ -1,8 +1,7 @@
 //! Post-processing tools
 use coremem::meas::AbstractMeasurement;
 use coremem::render::{ColorTermRenderer, Renderer as _, RenderConfig, SerializedFrame};
-use coremem::sim::StaticSim;
-use coremem::sim::legacy::SimState;
+use coremem::sim::legacy::{SimState, StaticSim};
 
 use itertools::Itertools as _;
 use lru::LruCache;