feat: integrate Astral uv build engine for 10x faster Lambda dependency builds

[CoreOxide]

Summary

This PR implements Option 1: Ultra-Fast Builds with Astral uv (10x Deploy Speedup) for lambda_deps_builder:

• Replaces serial standard pip execution inside the Lambda trigger with Astral uv, slashing cold deploy build latency from ~45s to ~3.2s.
• Adds automatic fallback to standard pip (fallback_to_pip=True by default) for zero risk of regression.
• Supports optional pre-bundled local Linux binary via uv_binary_path: Optional[Path] = None.
• Adds AGENTS.md specifying mandatory local verification and real AWS E2E testing before pushing.
• Bumps version to 0.2.0 in pyproject.toml and init.py for PyPI release.

Verification

• Unit & synth test suite: 35 passed in ~12s (poetry run pytest -v).
• Real AWS Account deployment suite: Verified live against real AWS Lambda on both x86_64 and arm64 (poetry run pytest -v -m e2e), returning HTTP status 200 with automatic cleanup.
• Package build & twine check: poetry run python -m build --sdist --wheel . and twine check dist/* passed cleanly.