docs(tasks): complete Relay lifecycle release

[artem-korolev]

Summary

• record the successful 3.1.0 Rush Delivery release
• record npm registry and live tarball verification
• record the successful Docusaurus Pages deployment
• move the completed lifecycle task into tasks/completed
• repair relative task links for the completed-task location

Release evidence

• implementation PR feat(webapp-graphql-relay): add route query lifetime ownership #4 passed validation and merged as 213494b
• Rush Delivery completed and generated version commit 75746a7
• @omgjs/labkit-webapp-graphql-relay@3.1.0 is npm latest
• the live tarball has the exact Relay peers, no private Relay dependencies, the lifetime-first declarations, and deprecated compatibility declaration
• the GitHub Pages build and deployment completed successfully

Validation

• git diff --check
• all relative links in the completed task resolve