Spec: Release-driven downstream update propagation across PSModule repositories

[MariusStorhaug]

Supersedes PSModule/Process-PSModule#374.

Goal

Define the org-level release-management specification for propagating version bumps when a shared PSModule dependency (GitHub Action/module) releases.

Scope

• Trigger on
  elease.published in producer repositories.
• Enumerate downstream consumers.
• Create per-consumer anchor issue + bump PR in consumer repo.
• Link anchors into a central tracking issue for live rollout status.
• Support both maintainer/agent PRs and Dependabot-origin PRs.
• Define progress/closeout behavior using sub-issue summaries.

Why this belongs in docs

This is cross-repository release-management policy and automation design, not specific to Process-PSModule implementation.