Enforce main branch checks and finalize integration evidence #17

Goal

Protect main with the existing PR checks and align documentation with the successful hosted smoke run.

Scope

• Configure an active main branch rule requiring pull requests and successful checks.
• Require these existing checks:
  • Tests and package (Python 3.11)
  • Tests and package (Python 3.13)
  • Release check
• Require the branch to be up to date and review conversations to be resolved.
• Block force pushes and branch deletion.
• Document the solo-maintainer review process and any owner bypass.
• Record hosted acceptance from run https://github.com/DimitryZH/container-platform/actions/runs/40046455406.
• Update README, roadmap and manual workflow documentation to remove outdated pending-acceptance statements.

Acceptance criteria

• An active rule targets main and requires PRs plus all three named checks.
• Force pushes and branch deletion are blocked.
• Review requirements are explicit and usable by a solo maintainer; self-approval is not presented as independent review.
• Any bypass permissions are documented accurately.
• A documentation PR demonstrates that the required checks are attached and enforced.
• Hosted evidence identifies the tested commit, candidate hash, successful runtime and verified cleanup.
• Legacy ineligibility and unverified live cancellation recovery remain explicit.
• Documentation reflects the implemented milestone scope.

Boundaries

Manual runtime smoke remains optional and is not a required PR check.

Repository settings are configured by the owner. Milestone closure is a separate decision after verification.

Related to #15.