chore: prepare AgentCore 0.17.0 release

[zhanghanduo]

Summary

• Prepare AgentCore 0.17.0 from the merged PR fix(loop): make runaway recovery reach Anthropic and stop treating it as no_tool #77 feature fragment.
• Update the package version, lockfile, and changelog; consume the fragment.

Verification

• python3 scripts/version.py --check-tag v0.17.0
• python3 scripts/check_version_bump.py --base origin/main
• uv lock --check
• uv run ruff check agent_core tests scripts
• uv run pyright agent_core
• uv run pytest -q (2327 passed, 1 skipped)
• uv build and twine check dist/*
• Clean-environment wheel install and import smoke test

After CI passes, merge this release preparation PR, then tag the resulting main commit as v0.17.0 to trigger the release workflow.