Reflection follow-up: resolve duplicate LEARNINGS.md (workspace root vs memory/)

The 6/14 audit subagent flagged ~/agents/will-engineer/memory/LEARNINGS.md as missing per LEARNINGS-PROTOCOL.md, and Track A wrote a 10.8 KB summary fabrication to that path. But the canonical institutional-memory scroll has lived at ~/agents/will-engineer/LEARNINGS.md (workspace root) since 4/21 with 9+ months of dated entries. There are now two LEARNINGS.md files. Fix: (1) delete ~/agents/will-engineer/memory/LEARNINGS.md (the duplicate summary), (2) open agent-infra PR to update ~/shared-knowledge/LEARNINGS-PROTOCOL.md lines 11 and 35 to reference ~/agents/<agent>/LEARNINGS.md (workspace root) instead of memory/LEARNINGS.md. The protocol-doc fix routes through agent-infra because ~/shared-knowledge/ is rsync-managed (sync-shared-knowledge.sh hourly clobber from agent-infra repo). Cross-reference: 6/15 LEARNINGS entry under #What went wrong#. Priority 3 (operational hardening).