Purpose
-------
Regression tests for :class:`oct.core.progress.ProgressTracker` and
:class:`oct.core.progress.Dashboard`.
Responsibilities
----------------
- Verify ProgressTracker lifecycle (start, complete, fail, skip) and markers.
- Verify Dashboard in-place updates, timer, quiet mode, and non-TTY fallback.
Diagnostics
-----------
Domain: CORE-TESTS
Levels:
L2 — test lifecycle
L3 — assertion details
L4 — deep tracing
Contracts
---------
- All output is captured via ``io.StringIO``; no real terminal writes.