[Portal] Align Doc & Storybook with Radix and deploy it on Skyrocket

[rachelleau]

Summary

• Retitle the five stories that used the components/v1 prefix. components/v1 was only a Storybook title, not a source folder. components/v2 stays, because that folder is the current component layer and its titles are derived from the path.
• Rewrite the portal UI docs, component guidelines, and the update-portal-ui skill so they describe Radix Themes and components/v2 instead of FluentUI components that are no longer in the app.
• Vendor @oursky/storybook-addon-comments and register it in Storybook. The repo is private, so it is installed with file:portal/vendor/storybook-addon-comments. The portal image Dockerfiles copy that tree before npm ci.
• Add a Skyrocket project, authgear-portal-storybook, under portal/. nginx serves the static Storybook build and proxies /api/ to a comments API backed by Postgres. Deploy with skyrocket deploy from portal/, without --env public.

Story titles are Storybook-only. Nothing in the portal app imports *.stories. portal/src/util/shades.ts and its golden fixtures are unchanged; deriveColors still uses them for brand button colors. This project does not deploy the Authgear server.

Test plan

• cd portal && npm run storybook
• Confirm the sidebar has no components/v1 group
• Confirm these titles: portal/LoginMethods/LoginMethodChooser, portal/LoginMethods/LoginMethodIcon, portal/LoginMethods/AuthenticationSection, components/CheckboxWithTooltip, portal/Users/AccountStatusDialog
• Confirm components/v2 stories still appear (Button, Callout, and the rest)
• On local Storybook, the Comments panel reports HTTP 404 because there is no /api/comments
• cd portal/comments-api && npm test
• cd portal && npm run typecheck
• After skyrocket deploy from portal/, curl -sS https://authgear-portal-storybook.oursky.dev/api/healthz returns JSON with schemaReady
• On that site, post, resolve, and delete a comment in the Comments panel

[tung2744]

@rachelleau Who is going to run the skyrocket deploy? Is that designer will run it manually and no ci is expected to run it?

[tung2744]

Added a commit to move the new dockerfile and nginx config into storybook directory