fetchOrSubstituteTree improvements
fetchOrSubstituteTree improvements

Caches tree in addition to lockedRef, and explicitly writes out the logic for different combinations of cached/uncached flakes and indirect/resolved/locked flakes. This eliminates uneccessary calls to lookupInFlakeCache, fetchTree, maybeLookupFlake, and flakeCache.push_back

rycee/nix,rycee/nix,NixOS/nix,rycee/nix,NixOS/nix,NixOS/nix,NixOS/nix,rycee/nix,NixOS/nix,rycee/nix