#2921 Docs: swamp skill says cancelling a parent run cancels its nested child runs; the child is left suspended

Description

The bundled swamp skill's execution-semantics reference describes nested-workflow cancellation incorrectly. The skill is what an agent reads to explain cancel behaviour, so it will tell users that cancelling the parent is enough.

.claude/skills/swamp/references/workflow/references/execution-semantics.md (around line 173) says:

Cancelling a run also cancels the child runs of its nested workflow steps. Over --server, cancel the parent's run id. A child run is not cancellable by its own id there.

Actual behaviour

Given a parent whose type: workflow step runs a child that is suspended at a manual_approval gate:

• The parent is suspended (swamp-club#2736).
• swamp workflow cancel parent --run <id> cancels and settles the parent. The nested step is recorded failed with Detached: the run ended ….
• The child run stays suspended.
• The CLI prints Nested run … was left unfinished. Cancel it with swamp workflow cancel child --run <child id>, and that command cancels the child.

Cascading the cancel is still open as swamp-club#2867, and swamp-club#2836 documents the current behaviour for the manual.

Expected

Until #2867 ships, the skill reference should say:

• the suspended child is detached and left suspended;
• the CLI prints the command that cancels it;
• the child must be cancelled under its own workflow name and run id.

The --server sentence in the same paragraph should be checked against current behaviour in the same change.

Found while end-to-end validating swamp-club#2895 (branch 8ae02e19).