The parallel item runs branches concurrently with sync:all or sync:any
policy and optional per-branch wait_for synchronization. Each branch
runs in its own daemon thread and produces a clean per-item entry in
the SQLite report; the live output is prefixed [<branch_name>] so
concurrent branches stay readable.
Supporting changes:
- StdoutProxy (lib/stdout_redirect.py): thread-aware sys.stdout/stderr
with per-thread capture buffers and per-branch live-output prefix.
Adds writeln() for Python 3.14 unittest compatibility.
- TestItemContainer: shared base extracted from Group/Cycle for the
sequential children execution pattern.
- TestItemSleep: interruptible loop polling _is_stopped so sync:any
can cancel slow branches quickly.
- TestReport: thread-safe SQLite (check_same_thread=False + lock).
Also drops the unused -m/--terminal mode and its module.
Validation: 11 scenarios in test/validation/items/parallel covering
sync:all/any, no_fail, wait_for + timeout, conditions, multi-branch,
nested parallel, parallel inside loop, real branch failure.
Documentation: new parallel_test_item.rst added to the manual.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
