- New: server/services/memory-service.js
  - saveSessionSummary(): auto-save session summary to short-term/
  - loadRecentMemory(): inject last 5 sessions into system prompt
  - appendToMemoryMd(): auto-append key facts with size control
- Modified: server/routes/agent-chat.js
  - buildSystemPrompt() now loads recent short-term sessions
  - Conversation completion triggers auto memory save
- Verified: CEO Agent conversation creates session file + updates memory.md