Add adversarial server clock control

[chubes4]

Summary

• add action-bound, capability-negotiated server clock transitions for WordPress Playground adversarial campaigns
• preserve transition ordering, per-case restoration, replay evidence, and fail-closed unsupported surfaces/backends
• terminalize non-cooperative timed-out cases without running later cases on a shared runtime

Verification

• npm run build
• npm run test:adversarial-runtime (24 tests)
• git diff --check

Fixes #2263.

AI assistance

• Model: GPT-5.6 Sol
• Tool: OpenCode
• Used for: implementation, adversarial contract review, and deterministic test execution. Chris Huber reviewed and remains responsible for every line.