Map from (script, leaf_version) to (sets of) control blocks. More than one control block for a given script is only possible if it appears in multiple branches of the tree. We keep them all so that inference can reconstruct the full tree. Within each set, the control blocks are sorted by size, so that the signing logic can easily prefer the cheapest one.
Declared in <script/signingprovider.h>
std::map<std::pair<std::vector<unsigned char>, int>, std::set<std::vector<unsigned char>, ShortestVectorFirstComparator>> scripts;