stream-clone: introduce the notion of an experimental "v3" version We introduce a new experimental "v3" stream protocol, disabled by default. In practice the "v3-exp" protocol introduced in this changeset is identical to v2, but this changeset, lay the groundwork for having a new protocol: configuration, capability exchange, test coverage, etc. The actual protocol work will starts in the coming changesets.

--- a/mercurial/configitems.py	Sat May 20 01:39:13 2023 +0200
+++ b/mercurial/configitems.py	Fri May 19 14:49:50 2023 +0200
@@ -1298,6 +1298,11 @@
 )
 coreconfigitem(
     b'experimental',
+    b'stream-v3',
+    default=False,
+)
+coreconfigitem(
+    b'experimental',
     b'treemanifest',
     default=False,
 )