openrig-cmux

cmux is a provider for OpenRig views — the same rig terminal surface as herdr, rendering the tiles into cmux instead. It is the provider OpenRig already shipped (the existing "Launch in cmux" affordance generalizes onto rig terminal <provider>), kept working. The OpenRig-semantic half is identical to openrig-herdr: OpenRig decides which agents form a view; the provider renders the pixels. Read openrig-herdr first for the full model — this skill only calls out what differs for cmux.

Provider status — cmux is best-effort

• herdr is the default and the proof-gated provider; cmux is best-effort — it ships on the same rig terminal <provider> + web-launcher neighborhood, but a cmux miss is not a slice failure. Reach for cmux when it is specifically wanted; otherwise default to herdr (rig terminal open <view> with no --provider).
• Views are provider-agnostic: the same view + the same agents + the same semantics carry across herdr and cmux. A saved view opens in either.

The surface (same three verbs, --provider cmux)