fix(engine): ENGINE_DECISION_GUARDRAIL_GLOBS omits the guardrail-matching engine itself and the gate-advisory/predicted-gate orchestrator files

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⚠️ Definition of Done: this issue must be completed in full, in a single PR. Do not split this
work across multiple PRs, and do not defer any Deliverable below to a follow-up issue. A PR that
satisfies only some of the Deliverables, stubs a required test, or leaves a checkbox
partially-done does NOT resolve this issue and will be closed.

Context

packages/loopover-engine/src/review/guardrail-config.ts:24-54's ENGINE_DECISION_GUARDRAIL_GLOBS
explicitly lists both the host-side shim and the real engine-package path for two file pairs (e.g.
src/settings/autonomy.ts + packages/loopover-engine/src/settings/autonomy.ts at lines 34-35;
src/review/guardrail-config.ts + its own engine path at lines 49-50), with comments explaining why
both are needed: a PR could otherwise weaken the real logic by only touching the engine-side file,
which wouldn't itself trip the hard-guardrail hold.

That same "list both sides" treatment was never extended to:

• packages/loopover-engine/src/signals/change-guardrail.ts — the file that actually implements
  isGuardrailHit (line 165) and guardrailPathMatches (line 139), i.e. the guardrail-matching
  engine itself.
• packages/loopover-engine/src/advisory/gate-advisory.ts — gate-decision core logic and the
  check-run sanitizer (see the sibling issue filed alongside this one for a specific drift bug
  there).
• packages/loopover-engine/src/predicted-gate.ts — the orchestrator wiring both together.

src/rules/** (line 25) covers the host's src/rules/advisory.ts, but no
packages/loopover-engine/src/advisory/** or packages/loopover-engine/src/signals/** entry exists
anywhere in the guardrail glob list.

Consequence: resolveHardGuardrailGlobs/isGuardrailHit (via src/queue/processors.ts:2068 and
packages/loopover-engine/src/predicted-gate.ts:285-286,315) decides whether a PR is forced into
manual-review hold instead of being auto-mergeable by the one-shot gate. A contributor PR that edits
only packages/loopover-engine/src/signals/change-guardrail.ts (e.g. weakening the glob matcher to
always return false) or packages/loopover-engine/src/advisory/gate-advisory.ts (e.g. changing
block/advisory dispositions) would not itself trip the hard guardrail — a self-referential blind
spot in exactly the mechanism meant to catch this class of change.

Requirements

• Add packages/loopover-engine/src/signals/change-guardrail.ts,
  packages/loopover-engine/src/advisory/gate-advisory.ts, and
  packages/loopover-engine/src/predicted-gate.ts to ENGINE_DECISION_GUARDRAIL_GLOBS, matching
  the existing "list both host and engine path" pattern and its documented rationale.

Deliverables

• ENGINE_DECISION_GUARDRAIL_GLOBS includes all three newly-identified engine-package files.
• A new test calls isGuardrailHit(["packages/loopover-engine/src/signals/change-guardrail.ts"], resolveHardGuardrailGlobs(null)) and asserts it now returns true — currently false.
• A new test does the same for packages/loopover-engine/src/advisory/gate-advisory.ts.
• A new test does the same for packages/loopover-engine/src/predicted-gate.ts.

All four Deliverables are required in the same PR.

Test Coverage Requirements

packages/loopover-engine/** is measured by codecov/patch (99%+ target, branch-counted). The
three new tests must exercise each previously-uncovered file path directly against
isGuardrailHit.

Expected Outcome

A PR touching the guardrail-matching engine itself, the gate-decision advisory core, or the
predicted-gate orchestrator correctly trips the hard guardrail hold, closing a self-referential
blind spot in the mechanism meant to catch exactly this class of change.

Links & Resources

• packages/loopover-engine/src/review/guardrail-config.ts:24-54
  (ENGINE_DECISION_GUARDRAIL_GLOBS, the list to extend)
• packages/loopover-engine/src/signals/change-guardrail.ts:139,165 (isGuardrailHit,
  guardrailPathMatches)
• packages/loopover-engine/src/advisory/gate-advisory.ts, packages/loopover-engine/src/predicted-gate.ts:285-286,315
• src/queue/processors.ts:2068 (a real call site consuming this guardrail decision)
• See the sibling issue filed alongside this one for a specific, currently-live drift bug in
  gate-advisory.ts this same self-referential gap would have hidden from the guardrail

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JSO-6040