merge default in to stable evolve 4.0.0 is coming.

merge back into stable The 2,7 is meant to be a subset of stable.

prepare a branch for compatibility with mercurial 2.7 to 3.0(.0) Evolve 4.0.0 is coming

test: update to output change introduced by future 3.1

simple4server: backport the bundle2 exchange

evolve: install progress support for the bundle2 pull path The custom wireprotocol command had a trick to display progress while pulling. We reinstall such logic for the new path using bundle2. Its notable that we are using the bundle2 advisory parameter for this purpose.

evolve: install progress support for the bundle2 push path The custom wireprotocol command had a trick to display progress while pushing. We reinstall such logic for the new path using bundle2.

evolve: add a pull path using bundle2 Instead of using a dedicated wireprotocol commands, we use bundle2 to transmit an obs marker parts. This aims at both testing bundle2 more and to limit the amount of special code we needs to put in simple for server to fit our needs. The massive test changes comes from the fact we can use this fast path for both remote and local push.

evolve: advertise obsmarker creation in the transation hook This will let extensions hooks on marker exchange.

evolve: add bytes and new marker data when processing part This will helps use to keep printing useful message when pulling through bundle2.