* test(#2770): empty contextPath argument must fail closed, not green-skip the decision-coverage gate
The handler conflated empty-arg (caller error) with file-missing (legitimate skip),
returning passed:true/skipped on an empty argument. Add: empty arg → passed:false;
real-path-to-absent-file → legitimate green skip preserved; omitted arg → fail closed.
* fix(#2770): decision-coverage gate fails closed on empty arg + workflow recomputes CONTEXT_PATH in-block
Handler (check-command-router.cts): split the guard — empty/missing contextPath
argument is a caller error (fail closed, passed:false, mirrors #1365); a real path
whose file genuinely does not exist keeps the legitimate green skip.
Workflow (plan-phase.md): recompute CONTEXT_PATH inside the consuming Bash block
(it was set in the step-1 init block, which does not survive into the separately-
spawned gate block — so the gate ran with an empty arg and silently green-skipped).
* chore(#2770): changeset fragment
* fix(#2770): guard workflow empty-glob case (review blocker) + update drift-guard test
The handler now fails closed on an empty contextPath arg, so the workflow's
unguarded glob (empty when a phase genuinely has no CONTEXT.md) would invoke the
gate with an empty arg → passed:false → exit 1, hard-halting the legitimate
'Continue without context' plan-phase path. Guard the empty-glob case: only run the
gate when a CONTEXT.md actually exists. Update the F1 drift-guard test (which gave
false coverage — it only checked for the ${CONTEXT_PATH} token) to assert the
in-block recompute AND the empty-glob guard.
* fix(#2770): keep plan-phase.md under ADR-857 size cap + ack emitted drift + fix drift-guard window
The workflow fix grew plan-phase.md past the ADR-857 phase-6 size cap (94519B) and
triggered emitted-attribution. Condense adjacent §13a prose/JSON to offset (net
+89B, under cap). Add tests/emitted-drift-ack.json acknowledging the residual growth.
Widen the drift-guard test window (the gate invocation is now nested in the empty-glob
guard, so the old 400-char window missed the glob recompute).
* chore(#2770): backfill changeset PR number (2881)
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Co-authored-by: Test <test@example.com>
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