Issue #3611246: Surface a workflow-authored status on the requester's process list

Follow-up to #3611212. Lets a workflow author narrate the requester-facing status instead of showing a technical step label.

A render-only message node gains an optional, translatable Status label (separate from the body: a node may carry a body but no status). The "My requests" list shows the current status, resolved from the chain the instance is on; for a completed instance it comes from the terminal end node, so a final outcome ("Approved"/"Rejected") is a status on distinct end nodes. With no status authored, the list shows only the lifecycle badge, never a node label.

• orchestra (base): neutral InstanceStatusProviderInterface + orchestra.instance_status collector, so a surface reads a status without depending on any provider module.
• orchestra_interaction: the Status field on the message interaction, a StatusBearingInteractionInterface, and a tagged provider (latest chain status, honoring reset; terminal end node when completed).
• orchestra_ui: the card shows the author status, consuming only the base collector (no orchestra_ui -> orchestra_interaction dependency).

Kernel tests cover the resolver and the card; docs and French translations included.

Fixes #3611246.