宜博 / lemonboss

Root cause: heartbeat.md instructed Master to append inspection logs to
plan.md on every heartbeat, causing plan.md to grow to 209KB (2922 lines
of repeated 'status stable' logs).

Changes:
1. Truncated master/plan.md from 209KB to 7KB (kept pipeline records,
   removed 2800+ lines of repeated heartbeat logs)
2. Updated heartbeat.md rules:
   - Banned appending inspection logs to plan.md
   - Added token budget awareness (10KB file read limit, prefer grep/find)
   - Normal heartbeats should reply '[心跳正常]' without using tools

- Moved data/system/ → system/ (agents, templates, skills, data, workspace)
- Updated all server route/service path references
- Updated all script path references
- Updated all documentation references
- Restructured .gitignore for cleaner system/ vs data/ boundary

system/ = platform-shared assets (system agents, template library)
data/ = tenant-specific company instance data