feat(dashboard): say Add your website instead of Create website
Release of staging commit 43696342f (cherry-picked with -x).
Website CTAs used four different labels: "Create website", "Create your first website", "Add a website" and "Add website". They now follow one rule:
- Header and toolbar buttons (Home, Websites, workspace settings): Add website
- Empty states, the dialog title, the onboarding form, Home's setup prompt, and the Databunny / business-context links: Add your website. The dialog submit button reads Add website, and the pending state reads "Adding…".
- With no sites, Home shows its setup prompt at the top instead of a second "No websites yet" empty state under Website snapshot. That way Home has one add-website action besides the header button.
- "Back to Websites" is now "Back to websites", matching the other back links.
The E2E selectors in onboarding, website-setup, websites and utils/dashboard.ts are updated. The header button stays exact-matched as "Add website", so it can't collide with the empty state's "Add your website".
The staging-side docs fix (f9f61d304, which points "Sign in" at /login) isn't included because main already has it.
Verification: dashboard tsc clean, Biome clean, commit hooks pass. CI Dashboard Playwright runs the updated selectors.
Summary by cubic
Unifies the dashboard's website add CTAs: header and toolbar buttons now say "Add website", while empty states, the dialog title, Home's setup prompt, and business-context links say "Add your website". Previously the dashboard mixed four labels ("Create website", "Create your first website", "Add a website", "Add website").
With no sites, Home now shows only its setup prompt and drops the redundant "No websites yet" empty state under Website snapshot. The dialog submit button reads "Add website" with an "Adding…" pending state, and "Back to Websites" is now "Back to websites". E2E selectors in onboarding, website-setup, websites, business-context, and utils/dashboard.ts were updated to match.