Mark Lemma 7.7.2 as completed (#466)

And now everything in the blueprint is green!

Author: Parcly-Taxel

blueprint/src/chapter/main.tex

@@ -6131,6 +6131,7 @@ \section{Forests}
 \end{lemma}
 
 \begin{proof}
+    \leanok
     By \Cref{densities-tree-bound} and the density assumption \eqref{forest4}, we have for each $\fu \in \fU$ and all bounded $f$ of bounded support that
     \begin{equation}
         \label{eq-explicit-tree-bound-1}