chore(cleanup): Remove old Prometheus monitoring data and build caches

CLEANUP PERFORMED:
1. Prometheus Data (6.2MB):
   - Removed data/ directory with TSDB blocks from July-August
   - Old time-series metrics data no longer needed
   - Directory is already in .gitignore

2. Turbo Build Caches (~236KB):
   - Removed all .turbo cache directories
   - Cleaned caches from packages and node_modules
   - Will be regenerated on next build

3. Old Log Files:
   - Removed 6 stale log files from packages/agents
   - test-output-with-fixes.log
   - spotbugs-investigation-*.log
   - v9-raw-output-30percent.log
   - brave-research-output.log
   - v9-fixed.log
   - fresh-report-run.log

4. Test Outputs (105MB):
   - Cleaned from 504 → 15 files (completed in previous commit)
   - Kept last 10 of each type

DISK SPACE FREED:
- Total: ~111.5MB freed
- Project remains at 1.4GB (mostly node_modules)

NOTES:
- All deletions are safe - no active/needed files removed
- Cleanup script will maintain this going forward
- Reports directory kept (active files from today)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: alpsla