Submit extension proposal to Quarkiverse

[t1]

Sub-issue of #28. Depends on #29 (proposal draft).

MAINTAINER ACTION REQUIRED: This is a manual step that requires maintainer action.

Submit the extension proposal from #29 as an issue in quarkusio/quarkus following the Quarkiverse onboarding process.

Scope:

• Review the proposal document from Draft Quarkiverse extension proposal #29
• Create an issue in quarkusio/quarkus with the Extension Proposal template
• Wait for Quarkiverse team approval and repo creation
• Update this issue with the proposal issue link and new repo link

Completion criteria:

• Proposal issue created in quarkusio/quarkus
• Quarkiverse repo created at github.com/quarkiverse/quarkus-openapi-ui
• Maintainer has write access to new repo