v0.4.11: CI lints, tests and security-scans before building the image

CI now lints, tests, and security-scans the code before building the image, via
the generic reusable code-workflow.

- New code pipeline job runs make lint (flake8 + mypy), make test (pytest unit +
  docker-in-docker integration), and make sec, and the image build now waits on
  it. The pipeline previously built and published the image without running any
  of these.
- New make sec: semgrep, bandit and pip-audit run in parallel and their findings
  merge into sec.sarif for the GitHub Security tab. It never fails the build;
  findings are reported, not gated. The scanners live in an isolated venv in the
  dev image so semgrep's bundled mcp pin cannot collide with the project's
  mcp==1.9.0.
- Removed the make check alias; use make lint, make test, make sec.
- Kept .telemetry/ out of git and out of the image.