feat: add harness progress summaries

[cafitac]

Summary

• add a top-level progress block to harness-style auto/compile reports in CLI, SDK, and MCP
• keep the existing final_crawl_result payload, but expose the most operator-relevant counters in a stable summary block
• align empty-page expectations with existing runner semantics (pages_completed=1, pages_failed=0)

Testing

• uv run --extra dev pytest tests/unit/sdk/test_client.py tests/unit/mcp/test_tools.py tests/unit/cli/test_auto_command.py tests/unit/cli/test_compile_command.py -q
• bash scripts/check-python.sh
• bash scripts/verify-ai-harness.sh
• uv run --extra dev python - <<'PY' ... auto progress smoke ...