feat(hygiene): anti-redundancy enforcement — spec rules + weekly audit

Root cause analysis of the 2026-07-20 redundancy incident:
1. No single-source-of-truth rule -> same file legitimately lived in 4+
   locations, diverging silently
2. Relative path resolution (Path(__file__).parent/'data') -> each
   hardlinked copy of mofin_db.py pointed to a DIFFERENT database
3. 'Backup habit' left .bak/legacy files in production dirs, which
   monitoring then scanned and reported as false alarms
4. Half-done migrations: DB tables created but old JSON writers/readers
   stayed (price_events), old files stayed
5. Dead modules never got buried: xiaoguo 'dead' but bot ran 8 days
   as root eating 2.5GB
6. Monitoring checked 'does it exist' not 'is it alive' -> stale file
   mtime reported as 'pipeline stalled 14 days' (false alarm)
7. No 'system hygiene' as a check category at all

Prevention implemented:
- dev-spec.md v2.0: 五条红线 -> 十条红线
  #6 single source of truth (hardlink only, no independent copies)
  #7 absolute data paths only (no __file__-relative data resolution)
  #8 no backups/legacy in production data dirs (archive immediately)
  #9 dead module burial checklist (6 mandatory steps)
  #10 monitor liveness (DB table freshness) not existence
- File Location Constitution: canonical location per content type
- NEW system_hygiene_audit.py: weekly Monday 07:30 cron checking
  diverged copies / broken hardlinks / zombie processes / orphan data
  files / dead cron scripts / DB freshness -> hygiene_report.json + XMPP
- specs/hygiene.json: module spec per red line #1
- Verified: audit found 5 real issues on first run, all fixed, re-run clean

scripts/merge_third_db.py

@@ -0,0 +1,94 @@
+import sqlite3, os, shutil
+from datetime import datetime
+
+THIRD = '/home/hmo/.hermes/profiles/position-analyst/scripts/data/mofin.db'
+MAIN = '/home/hmo/MoFin/data/mofin.db'
+BACKUP = f'/home/hmo/MoFin/archive/third-db-backup-{datetime.now().strftime("%Y%m%d-%H%M")}'
+os.makedirs(BACKUP, exist_ok=True)
+shutil.copy(THIRD, os.path.join(BACKUP, 'mofin.db'))
+print('backup:', BACKUP)
+
+t = sqlite3.connect(THIRD, timeout=10)
+m = sqlite3.connect(MAIN, timeout=30)
+m.execute('PRAGMA busy_timeout=30000')
+
+# 1. sector_snapshots: dedup by (snapshot_id, name)
+existing = set()
+for r in m.execute("SELECT snapshot_id, name FROM sector_snapshots"):
+    existing.add((r[0], r[1]))
+print(f'main sector_snapshots keys: {len(existing)}')
+
+cols = ['snapshot_id', 'name', 'change_pct', 'up_count', 'down_count', 'net_inflow',
+        'lead_stock', 'lead_stock_change', 'volume', 'turnover']
+ins = 0
+skip = 0
+for r in t.execute(f"SELECT {', '.join(cols)} FROM sector_snapshots"):
+    if (r[0], r[1]) in existing:
+        skip += 1
+        continue
+    m.execute(f"INSERT INTO sector_snapshots ({', '.join(cols)}) VALUES ({','.join('?'*len(cols))})", r)
+    existing.add((r[0], r[1]))
+    ins += 1
+m.commit()
+print(f'sector_snapshots: inserted {ins}, skipped {skip}')
+
+# 2. market_snapshots: dedup by (timestamp, source)
+existing2 = set()
+for r in m.execute("SELECT timestamp, source FROM market_snapshots"):
+    existing2.add((r[0], r[1]))
+cols2 = ['timestamp', 'source', 'up_ratio', 'mood', 'created_at']
+ins2 = 0
+skip2 = 0
+for r in t.execute(f"SELECT {', '.join(cols2)} FROM market_snapshots"):
+    if (r[0], r[1]) in existing2:
+        skip2 += 1
+        continue
+    m.execute(f"INSERT INTO market_snapshots ({', '.join(cols2)}) VALUES ({','.join('?'*len(cols2))})", r)
+    existing2.add((r[0], r[1]))
+    ins2 += 1
+m.commit()
+print(f'market_snapshots: inserted {ins2}, skipped {skip2}')
+
+# 3. todos: third has 4 rows, main has 94 — check by title, insert missing (map to main schema)
+todos_t = t.execute("SELECT title, description, status, priority, source, fix_action, retry_count, note, created_at, updated_at FROM todos").fetchall()
+ins3 = 0
+for r in todos_t:
+    ex = m.execute("SELECT id FROM todos WHERE title=?", (r[0],)).fetchone()
+    if ex:
+        continue
+    m.execute("INSERT INTO todos (title, description, status, priority, source, fix_action, retry_count, note, created_at, updated_at) VALUES (?,?,?,?,?,?,?,?,?,?)", r)
+    ins3 += 1
+m.commit()
+print(f'todos: inserted {ins3}, skipped {len(todos_t)-ins3}')
+
+# 4. capital_flow_cache: keep whichever is newer
+t_row = t.execute("SELECT cache_json, updated_at FROM capital_flow_cache ORDER BY id DESC LIMIT 1").fetchone()
+m_row = m.execute("SELECT cache_json, updated_at FROM capital_flow_cache ORDER BY id DESC LIMIT 1").fetchone()
+if t_row and (not m_row or (t_row[1] or '') > (m_row[1] or '')):
+    m.execute("DELETE FROM capital_flow_cache")
+    m.execute("INSERT INTO capital_flow_cache (cache_json, updated_at) VALUES (?,?)", t_row)
+    m.commit()
+    print('capital_flow_cache: replaced with third (newer)')
+else:
+    print('capital_flow_cache: main is newer/equal, kept')
+
+# verify
+total = m.execute("SELECT COUNT(*) FROM sector_snapshots").fetchone()[0]
+total2 = m.execute("SELECT COUNT(*) FROM market_snapshots").fetchone()[0]
+print(f'after merge: sector_snapshots={total}, market_snapshots={total2}')
+
+m.close()
+t.close()
+
+# 5. 删除第三库（连同 data 目录里的其他残留）
+third_dir = os.path.dirname(THIRD)
+trash = '/home/hmo/trashbox/third-db-retired-20260720'
+os.makedirs(trash, exist_ok=True)
+shutil.move(THIRD, os.path.join(trash, 'mofin.db'))
+print('third db moved to', trash)
+for f in os.listdir(third_dir):
+    src = os.path.join(third_dir, f)
+    if os.path.isfile(src):
+        shutil.move(src, os.path.join(trash, f))
+        print('  also moved:', f)
+print('DONE')