A founding Current-profile Add commit (epoch 0 → 1) merged locally
with no group-message publication obligation
(refs/marmot/protocol-core/joining.md lines 21-30 — "the
founding-creation exception"; FOUND-01). Unlike "commit",
extraProposals is required: a founding Add with no Add proposals
has no reason to exist. There is no proposalRefs field — at epoch 0
there are no staged proposals to bundle by reference.
CR-03: the engine refuses this intent — throwing before any commit
is built, with no state change — unless the group is at epoch 0,
the local member is the sole occupied leaf, there are no unapplied
proposals, and extraProposals resolves to at least one proposal,
all of them Adds. refs/marmot/protocol-core/publish-lifecycle.md
line 77 limits the empty-publication-obligation exception to epoch 0
and its immediately following founding Add Commit.
Application intent when calling MarmotGroupEngine.send.