refactor: redefine deepen-plan as targeted stress test

plugins/compound-engineering/skills/slfg/SKILL.md

@@ -11,7 +11,10 @@ Swarm-enabled LFG. Run these steps in order, parallelizing where indicated. Do n
 
 1. **Optional:** If the `ralph-wiggum` skill is available, run `/ralph-wiggum:ralph-loop "finish all slash commands" --completion-promise "DONE"`. If not available or it fails, skip and continue to step 2 immediately.
 2. `/ce:plan $ARGUMENTS`
-3. `/compound-engineering:deepen-plan`
+3. **Conditionally** run `/compound-engineering:deepen-plan`
+   - Run the `deepen-plan` workflow only if the plan is `Standard` or `Deep`, touches a high-risk area (auth, security, payments, migrations, external APIs, significant rollout concerns), or still has obvious confidence gaps in decisions, sequencing, system-wide impact, risks, or verification
+   - If you run the `deepen-plan` workflow, confirm the plan was deepened or explicitly judged sufficiently grounded before moving on
+   - If you skip it, note why and continue to step 4
 4. `/ce:work` — **Use swarm mode**: Make a Task list and launch an army of agent swarm subagents to build the plan
 
 ## Parallel Phase