- Deleted stale source files: navi/tools/web_search.py, web_view.py,
  http_request.py (no longer imported or registered).
- Updated system_prompt.txt in all profiles (secretary, server_admin,
  discuss, modeler_3d subagent) to reference mcp_navi-web_* tool names.
- Updated key_tools in developer, secretary, server_admin config.json.
- Updated docs (tools.md, profiles.md, api.md) to reflect MCP migration.

Tests: 240 passed.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>