chore: standardize qcom repo maintenance

[AviKaufman]

Summary

• Modernize the package layout around src/qcom and refresh tests, examples, tutorials, workflows, and project config.
• Add repository standards, architecture documentation, roadmap ownership, preferred API names, compatibility aliases, and deprecation warnings.
• Close the active maintenance items with adapter-registry coverage, compatibility-alias audit tests, optional dependency CI coverage, tutorial execution hygiene, and Markdown roadmap updates.

Validation

• uv run --with ruff ruff format --check src tests examples scripts noxfile.py
• uv run --with ruff ruff check src tests examples scripts noxfile.py
• uv run --with mypy mypy
• uv run --with pytest pytest tests/test_public_facade.py tests/test_compatibility_aliases.py
• uv run --with pytest pytest tests/test_compatibility_aliases.py tests/controls/adapters/test_registry.py
• All example scripts run with .venv/bin/python.
• uv run --with nbformat --with nbclient --with ipykernel --with matplotlib --with pyarrow python scripts/validate_tutorials.py

Notes

• The untracked local AGENTS.md file was intentionally not included.
• Compatibility aliases are retained but deprecated until a formal removal policy is chosen.