replace vacuous pipe-python no-flags bundling test

Overview / Motivation

Auto-filed by the /daily Step-C parked-candidate routing pass (2026-07-09) from a recursion-guard-parked workflow-fix candidate raised on task #1190.

Goal

Replace/augment tests/test_workflow_lint.py test_workflow_lint_pipe_python_bundled_in_no_flags with a source-dispatch assertion or a planted-offender no-flags CLI run (the #712 pattern).

Workflow gap

• Bug observed: test_workflow_lint_pipe_python_bundled_in_no_flags pins no-flags bundling via exit-0-on-a-clean-tree, which is vacuous for the bundled-vs-opt-in distinction — it passes whether or not the check is in the no_flags dispatch (verified on main 2026-07-09: tests/test_workflow_lint.py:2122 still asserts only returncode==0 on a clean tree).
• Why it is a workflow gap: The opt-in-not-bundled shipping failure documented by #712 §4f can recur for the pipe-python check unnoticed; the stronger planted-offender/source-dispatch pattern already exists in the same file (e.g. :2619, :3449).
• Confidence (emitter): medium

Proposed change (candidate diff sketch — refine in planning)

• assert 'args.check_pipe_python or no_flags' in workflow_lint source (source-dispatch pin), or plant a *.sh offender in a tmp scripts dir and run the no-flags CLI expecting nonzero.

Scope / surfaces

• Primary target: tests/test_workflow_lint.py

Constraints / invariants

• Workflow-surface only. scripts/workflow_lint.py --check-asks passes; ruff on touched files passes.
• This session runs under EPM_WORKFLOW_FIX_SESSION=1 semantics (workflow_fix_target Provenance line) — it MUST NOT auto-route its own subagents' workflow-fix candidates.

Provenance

• workflow_fix_target: tests/test_workflow_lint.py
• fingerprint: 0dfb688a0385

Parked prose-followup on #1190, 2026-07-09T19:07:02Z (statistics critic on plan v2). confidence: medium.