Previously, signing in with a kind toggle when the account had no
tenant_settings row in the lab database returned 'Bu hesap için kayıt
bulunamadı'. For a freshly-imported isletmem user that has never opened
DLS, the right behaviour is onboarding — not a dead end.
resolveTenantOnLogin now distinguishes three states:
- no_tenants → redirect /onboarding?kind=<pill> (session stays)
- mismatch → real error naming the existing kind, session rolled back
- matched → existing tenant set as active, /dashboard
Onboarding page accepts ?kind= and the workspace form pre-selects it, so
the user keeps their login pill choice without re-picking. Also fixed the
'teams.total > 0' redirect — it now requires a tenant_settings row before
sending users off to /dashboard, otherwise users with cross-app teams but
no DLS workspace would bounce.