Inline browser runtime bundles

[chubes4]

Summary

• Deliver server-packaged browser runtime plugin ZIPs as inline data URLs so nested browser Playgrounds do not depend on parent loopback URLs.
• Preserve browser probe HTML and screenshot artifacts even when a page-side script throws.
• Tighten REST schema fragments that emitted warnings under newer WordPress schema validation.

Testing

• npm run build
• npm run browser-probe-artifact-smoke
• npm run wordpress-plugin-smoke
• Verified through Studio Web live browser probe: runtime-mprmyz07-vqluf1

AI assistance

• AI assistance: Yes
• Tool(s): OpenCode (gpt-5.5)
• Used for: Diagnosed nested Playground runtime delivery failures from browser artifacts and drafted the focused runtime packaging/schema/artifact-capture changes; Chris remains responsible for review and merge.