mercurial: bump hg-evolve

.hgignore: remove ruff cache

project: removed some unneeded files

linting

core: make binary envelope behave like bytes type object for serialization and internal API usage. We would need to unpack it otherwise manually

.hgignore: add .venv to ignore dirs

nix: drop default.nix

nix: remove pkgs patches

deps: make dev-env build faster and cache rc_testdata

protocol: introduced binaryEnvelope to return raw bytes via msgpack