BFX04-01: Check that GPUd or Sentinel is running

**Requirement:** BFX04

Check that GPUd or Sentinel is running

**Priority:** P1

**Source:** software-reference-requirements (NSRG), not offtake.
**Plan status:** approved / published_version pending.
**Legacy ID:** BFX-XX-01.
**Action:** Implement net-new validation stubs (suite wiring + my-isv template + constraints) so a third party can fork and implement for their system.