chore: prepare v1.1.0 release

[TacoRocket]

What changed

Prepare the v1.1.0 release boundary for the completed grounded post-Phase-3 tranche.

This updates the package and schema version to 1.1.0, adds the v1.1.0 changelog entry, refreshes golden schema_version metadata, and removes internal-only roadmap/release-process docs from the public repo now that those references live in the external maintainer notes.

Why

The grounded follow-on tranche is complete and the branch has already passed the tranche-wide clean-context review plus the release validation and packaging checks.

Validation

• clean-context tranche review: no implementation-vs-plan drift found
• python3 -m ruff check src tests scripts
• PYTHONPATH=src python3 -m pytest tests/test_collectors.py tests/test_golden_outputs.py tests/test_contract_schemas.py tests/test_cli_smoke.py tests/test_help.py tests/test_terminal_ux.py tests/test_models.py -q
• PYTHONPATH=src python3 -m pytest -q
• python3 -m build --no-isolation
• python3 -m twine check dist/*
• fresh-venv wheel smoke test with fixture-mode whoami