#1021 hwec dsl-prompt fails in the deployed image: engine/cli/DSL_PROMPT.txt is not in the highway-core package data

EARS: When highway-core is installed from its wheel (the Docker image does uv pip install ./docker/highway-core), engine/cli/DSL_PROMPT.txt shall be installed next to engine/cli/hwec.py. Evidence (2026-10-20): docker exec highway-api hwec dsl-prompt -> 'Error: DSL prompt file not found at /opt/venv/lib/python3.13/site-packages/engine/cli/DSL_PROMPT.txt'. tests/unit/test_dsl_prompt_template_forms_992.py[core] fails in CI for the same reason (reads the prompt via engine.cli.__file__). Fix (uncommitted, with the #918 CI batch): docker/highway-core/pyproject.toml [tool.setuptools.package-data] engine += cli/DSL_PROMPT.txt. Wheel built from engine 010ea03 lists no DSL_PROMPT file; with the change it lists engine/cli/DSL_PROMPT.txt. Takes effect in production only after the next image build (CI).