refactor(ci): use shared Renovate actions

[denifilatoff]

Why

The canonical Renovate lint workflow duplicates validation, dependency lookup, and issue-monitoring
shell logic in every repository that receives the template. The tested implementation now lives in
the companion Workflow Hub PR:
Netcracker/qubership-workflow-hub#951.

What

• Replace the inline shell blocks with the three shared Renovate actions.
• Preserve the three jobs, event conditions, weekly schedule, Renovate image, permissions, outputs,
  health opt-out, and issue lifecycle.
• Keep repository-specific policy tests in consumer workflows rather than moving them into the
  shared actions.
• Document that the actions form one workflow contract and that Renovate updates their pinned
  release references.

The draft pins commit 77786061d16fabdb6e089c2ba1c5846da3efc62a from Workflow Hub PR #951 so
reviewers can inspect and test the exact implementation. Do not merge this PR with that temporary
pin. After #951 merges and Workflow Hub publishes a release, replace all three references with the
release commit SHA and trailing SemVer comment.

How to verify

• The template contract check confirms three jobs, remote action references, job-result propagation,
  and no remaining inline shell steps.
• Repository Super-Linter passes for the changed workflow and documentation.
• Healthy organization run:
  34103680003.
• Controlled failure and health issue creation:
  34103903676.
• Recovery and automatic issue closure:
  34104130674.

Dependency

Depends on
Netcracker/qubership-workflow-hub#951.