Squashed commit of the following:

commit dec7ca6b96c58decf2c5e5194b665fa2342951b2
Author: itsmattkc <34096995+itsmattkc@users.noreply.github.com>
Date:   Wed Feb 8 12:32:12 2023 -0800

    moved previewautocacher to rendermanager

commit d289d74d82c3911f3fdaa707abe9994c7363594d
Merge: a8a049a28 70d34c674
Author: itsmattkc <34096995+itsmattkc@users.noreply.github.com>
Date:   Wed Feb 8 12:15:31 2023 -0800

    Merge branch 'master' into move-cacher-to-renderman

commit a8a049a2857c438cbab0f1ab21e3299fdfbf1fa1
Author: itsmattkc <34096995+itsmattkc@users.noreply.github.com>
Date:   Wed Feb 8 11:18:25 2023 -0800

    initial work

app/render/rendermanager.h

@@ -29,6 +29,7 @@
 #include "node/graph.h"
 #include "node/output/viewer/viewer.h"
 #include "node/traverser.h"
+#include "render/previewautocacher.h"
 #include "render/renderer.h"
 #include "render/renderticket.h"
 #include "rendercache.h"
@@ -200,6 +201,16 @@ public:
     return backend_;
   }
 
+  PreviewAutoCacher *GetCacher() const
+  {
+    return auto_cacher_;
+  }
+
+  void SetProject(Project *p)
+  {
+    auto_cacher_->SetProject(p);
+  }
+
 public slots:
   void SetAggressiveGarbageCollection(bool enabled);
 
@@ -238,6 +249,8 @@ private:
 
   std::list<RenderThread *> render_threads_;
 
+  PreviewAutoCacher *auto_cacher_;
+
 private slots:
   void ClearOldDecoders();