Estimates with status Inserted (provider hasn't worked on them yet)
were showing up in the client's "Mes devis à valider" list. The
asclient endpoint now requires ProviderValidationDate to be set, so
only estimates the provider has actually established and submitted
are visible to the client. The asprovider endpoint is unchanged
(providers still need to see incoming unprocessed requests).
Also fix the anonymous-access redirect on Yavsc.Org: the application
cookie's LoginPath defaulted to /Account/Login, which has no
controller. Anonymous hits to a restricted page now redirect to the
real /signin endpoint (with /signout and /Account/AccessDenied set
to match the existing controller routes).
Co-Authored-By: Claude Code <noreply@anthropic.com>
