perf(emacs/lean-server): speed up task overlays
perf(emacs/lean-server): speed up task overlays

digama0/lean,dselsam/lean,digama0/lean,leanprover/lean,leanprover/lean,avigad/lean,leanprover-community/lean,fpvandoorn/lean,leanprover-community/lean,leodemoura/lean,avigad/lean,Kha/lean,johoelzl/lean,leanprover/lean,leanprover-community/lean,rlewis1988/lean,rlewis1988/lean,avigad/lean,fpvandoorn/lean,rlewis1988/lean,leanprover/lean,johoelzl/lean,rlewis1988/lean,leanprover-community/lean,leanprover-community/lean,Kha/lean,dselsam/lean,avigad/lean,rlewis1988/lean,fpvandoorn/lean,rlewis1988/lean,Kha/lean,fpvandoorn/lean,dselsam/lean,leodemoura/lean,fpvandoorn/lean,leodemoura/lean,digama0/lean,johoelzl/lean,johoelzl/lean,johoelzl/lean,johoelzl/lean,avigad/lean,Kha/lean,fpvandoorn/lean,Kha/lean,digama0/lean,leanprover/lean,digama0/lean,leanprover-community/lean,leanprover/lean,Kha/lean,dselsam/lean,leodemoura/lean,dselsam/lean,avigad/lean,leodemoura/lean,leodemoura/lean,digama0/lean,dselsam/lean