feat(pi-workflow): add lifecycle slash commands

docs/pi-workflow/README.md

@@ -4,7 +4,15 @@
 
 ## Start a feature
 
-Ask the assistant to use `pi_workflow` with:
+Start with:
+
+```text
+/workflow start <message>
+```
+
+The command sends the message through the assistant, which chooses the descriptive feature name and idempotency key before invoking `pi_workflow` through the normal tool path. In interactive TUI mode, `/workflow start` without a message asks what you want to start working on. Non-interactive modes require the message in the command.
+
+You can also ask the assistant to use `pi_workflow` with:
 
 - `action: "start"`
 - `workflow: { mode: "feature" }` (or omit `workflow`)
@@ -31,13 +39,24 @@ The assistant must inspect the current run before each state-changing call and o
 
 Use `/workflow` for the focused-card dashboard. It lists runs attached to the current session and shows persisted status, progress, Gate, plan, report, branch, and worktree information.
 
-Use:
+Use `/workflow continue` to select a run with a pending fresh-session handoff or normal-compaction continuation. `/workflow resume` is an alias. A run ID may be supplied directly:
 
 ```text
 /workflow continue <run-id>
+/workflow resume <run-id>
 ```
 
-only when the dashboard or `pi_workflow` reports a pending fresh-session handoff or normal-compaction continuation.
+Selection requires interactive TUI mode. In non-interactive modes, provide the run ID.
+
+## Stop active work
+
+Use `/workflow stop` to abort an active (`running` or `waiting`) Workflow Run owned by the current parent session. If more than one is active, interactive TUI mode presents a selection list. A run can also be named directly, including in non-interactive modes:
+
+```text
+/workflow stop <run-id>
+```
+
+Terminal runs and runs owned by historical parent sessions are not offered. The misspelled `/worlflow` alias is not supported.
 
 ## Script modes