Onboard rocm-examples as First Pull Subscriber (Phase 1 E)

[HereThereBeDragons]

Phase: 1E
Labels: quartz, phase-1, onboarding
Blocked by: Phase 1 C (pull subscriber docs and template ready), Phase 1 D3 (TheRock instrumentation live, status.json being published)

Onboard rocm-examples as the first real pull subscriber, validating the pull
subscription model end to end with a real downstream project.

Tasks

• Coordinate with rocm-examples maintainers: share docs/pull-subscription.md
  and agree on which pipelines and architectures they want to poll
• rocm-examples adds a scheduled polling workflow using
  templates/subscriber-pull.yml as reference
• Validate that rocm-examples correctly receives and processes status.json
  from release-nightly/latest.json

[HereThereBeDragons]

First talk with @zichguan-amd for rocm-examples:

Current setup:

• Runs on the following archs: gfx1151, gfx110X-all (only gfx1100 runners)
• Only care about: rocm build, rocm test (if available)
• Use: tarballs, python wheels, for the future: rpm/deb