#8509 Revert "refactor: derive hosts and display name from config (#8494)"

Reverts #8494.

Two commits:

• git revert of the #8494 squash commit. One conflict, in packages/auth/src/server.ts, where #8354 rewrote the billing hooks. I kept main's version and undid only #8494's edits there.
• #8354 already imports NOREPLY_FROM and COMPANY.SUPPORT_EMAIL in four billing files. The revert removes both, so those files use the same literal strings as the rest of auth again (Superset <noreply@superset.sh>, support@superset.sh). The email text does not change.

Validation:

• bun run lint and bun run check:i18n pass.
• auth, shared and email tests pass.
• Typecheck of auth, shared, email, trpc, cli, desktop, api, web, marketing, docs and mobile gives the same 165 errors on this branch and on origin/main. They are the local better-auth inference errors and none is new. CI runs typecheck without them.

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Summary by cubic

Reverts #8494, so hosts and the desktop display name are again hardcoded to superset.sh instead of being derived from NEXT_PUBLIC_ROOT_DOMAIN/EXPO_PUBLIC_ROOT_DOMAIN.

Refactors

• Drops the app-identity and email/sender helpers and the ROOT_DOMAIN, EMAIL_SENDING_DOMAIN, and RELAY_BACKUP_URL env vars; deploy workflows no longer pass them.
• Inlines CANONICAL_URLS and COMPANY constants as literal URLs like https://app.superset.sh.
• Desktop about panel, menus, and notifications use app.name/productName again, and the localized {displayName} strings are removed.
• Email from/to addresses are inlined as literals with no change to message content.

Summary by CodeRabbit

• Other Changes
  • Standardized links, service addresses, and email contact details across the app, desktop client, mobile app, CLI, and emails to use Superset’s published domains.
  • Desktop menus and notifications now use the app’s configured name.
  • Removed support for customizing protected-cookie domains; protection now applies to Superset domains and local addresses.