build: separate runtime and development dependencies

[FreeOnePlus]

Summary

• remove pytest, coverage, TOML parsing, lint, type-check, and build tooling from the production dependency path
• generate runtime and development requirements from independent pyproject layers
• enforce the boundary in tests and in a clean-wheel GitHub Actions smoke test

Validation

• Ruff: pass
• Mypy: pass (66 source files)
• Bandit: pass
• pytest: 1085 passed, 68 skipped; total coverage 57.90%
• coverage domains: protocol 89.94%, authentication 81.18%, core managers 81.84%
• clean Python 3.12 wheel install/CLI/import/runtime dependency audit: pass
• official MCP 2026-07-28 conformance: 25/25 passed
• real Doris Streamable HTTP + true subprocess Stdio: 11 passed
• temporary Doris tables/users after test: 0/0