feat(frontend): invite-based registration UI

- Add /register route with invite code prefill, password show/hide
- Add /login?registered=1 success banner
- Add /admin/invites page: list, create, revoke, copy link
- Add Einladungen nav section to admin sidebar (ADMIN_USER perm)
- Add invite error codes to errors.ts
- Add 48 i18n keys across de/en/es
- Update hooks.server.ts to allow public access to invite/register API

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/messages/de.json

@@ -640,5 +640,53 @@
 	"filter_operator_and": "UND",
 	"filter_operator_or": "ODER",
 	"filter_operator_and_label": "Alle gewählten Schlagworte müssen zutreffen (UND)",
-	"filter_operator_or_label": "Mindestens ein Schlagwort muss zutreffen (ODER)"
+	"filter_operator_or_label": "Mindestens ein Schlagwort muss zutreffen (ODER)",
+	"error_invite_not_found": "Einladungslink nicht gefunden oder ungültig.",
+	"error_invite_exhausted": "Dieser Einladungslink wurde bereits vollständig verwendet.",
+	"error_invite_revoked": "Dieser Einladungslink wurde deaktiviert.",
+	"error_invite_expired": "Dieser Einladungslink ist abgelaufen.",
+	"register_heading": "Konto erstellen",
+	"register_subtext": "Du wurdest eingeladen, dem Familienarchiv beizutreten.",
+	"register_label_first_name": "Vorname",
+	"register_label_last_name": "Nachname",
+	"register_label_email": "E-Mail-Adresse",
+	"register_label_password": "Passwort",
+	"register_prefill_hint": "Von deiner Einladung übernommen – du kannst es ändern",
+	"register_password_show": "Passwort anzeigen",
+	"register_password_hide": "Passwort ausblenden",
+	"register_btn_submit": "Konto erstellen",
+	"register_invalid_code": "Ungültiger Einladungslink",
+	"register_invalid_code_desc": "Dieser Einladungslink ist nicht gültig, wurde bereits verwendet oder ist abgelaufen. Bitte wende dich an den Administrator.",
+	"register_success": "Dein Konto wurde erfolgreich erstellt. Du kannst dich jetzt anmelden.",
+	"login_registered_success": "Dein Konto wurde erfolgreich erstellt. Melde dich jetzt an.",
+	"admin_tab_invites": "Einladungen",
+	"admin_invites_list_title": "Einladungen",
+	"admin_invites_empty": "Keine aktiven Einladungen vorhanden.",
+	"admin_btn_new_invite": "Neue Einladung",
+	"admin_btn_show_all": "Alle anzeigen",
+	"admin_btn_show_active": "Nur aktive",
+	"admin_btn_revoke": "Widerrufen",
+	"admin_btn_copy_link": "Link kopieren",
+	"admin_btn_copied": "Kopiert!",
+	"admin_invite_status_active": "Aktiv",
+	"admin_invite_status_exhausted": "Erschöpft",
+	"admin_invite_status_revoked": "Widerrufen",
+	"admin_invite_status_expired": "Abgelaufen",
+	"admin_invite_col_code": "Code",
+	"admin_invite_col_label": "Bezeichnung",
+	"admin_invite_col_uses": "Verwendungen",
+	"admin_invite_col_expiry": "Ablauf",
+	"admin_invite_col_status": "Status",
+	"admin_invite_col_link": "Link",
+	"admin_invite_unlimited": "∞",
+	"admin_invite_no_expiry": "Kein Ablauf",
+	"admin_new_invite_label": "Bezeichnung (z. B. für wen)",
+	"admin_new_invite_max_uses": "Max. Verwendungen (leer = unbegrenzt)",
+	"admin_new_invite_prefill_first": "Vorname vorausfüllen (optional)",
+	"admin_new_invite_prefill_last": "Nachname vorausfüllen (optional)",
+	"admin_new_invite_prefill_email": "E-Mail vorausfüllen (optional)",
+	"admin_new_invite_expires": "Ablaufdatum (optional)",
+	"admin_invite_created_title": "Einladung erstellt",
+	"admin_invite_created_desc": "Teile diesen Link mit der einzuladenden Person:",
+	"admin_invite_revoke_confirm": "Einladung wirklich widerrufen?"
 }

frontend/messages/en.json

@@ -640,5 +640,53 @@
 	"filter_operator_and": "AND",
 	"filter_operator_or": "OR",
 	"filter_operator_and_label": "All selected tags must match (AND)",
-	"filter_operator_or_label": "At least one tag must match (OR)"
+	"filter_operator_or_label": "At least one tag must match (OR)",
+	"error_invite_not_found": "Invite link not found or invalid.",
+	"error_invite_exhausted": "This invite link has already been fully used.",
+	"error_invite_revoked": "This invite link has been deactivated.",
+	"error_invite_expired": "This invite link has expired.",
+	"register_heading": "Create account",
+	"register_subtext": "You've been invited to join Familienarchiv.",
+	"register_label_first_name": "First name",
+	"register_label_last_name": "Last name",
+	"register_label_email": "Email address",
+	"register_label_password": "Password",
+	"register_prefill_hint": "Pre-filled from your invite – you can change it",
+	"register_password_show": "Show password",
+	"register_password_hide": "Hide password",
+	"register_btn_submit": "Create account",
+	"register_invalid_code": "Invalid invite link",
+	"register_invalid_code_desc": "This invite link is not valid, has already been used, or has expired. Please contact the administrator.",
+	"register_success": "Your account has been created. You can now sign in.",
+	"login_registered_success": "Your account was created successfully. Sign in now.",
+	"admin_tab_invites": "Invites",
+	"admin_invites_list_title": "Invites",
+	"admin_invites_empty": "No active invites.",
+	"admin_btn_new_invite": "New invite",
+	"admin_btn_show_all": "Show all",
+	"admin_btn_show_active": "Active only",
+	"admin_btn_revoke": "Revoke",
+	"admin_btn_copy_link": "Copy link",
+	"admin_btn_copied": "Copied!",
+	"admin_invite_status_active": "Active",
+	"admin_invite_status_exhausted": "Exhausted",
+	"admin_invite_status_revoked": "Revoked",
+	"admin_invite_status_expired": "Expired",
+	"admin_invite_col_code": "Code",
+	"admin_invite_col_label": "Label",
+	"admin_invite_col_uses": "Uses",
+	"admin_invite_col_expiry": "Expiry",
+	"admin_invite_col_status": "Status",
+	"admin_invite_col_link": "Link",
+	"admin_invite_unlimited": "∞",
+	"admin_invite_no_expiry": "No expiry",
+	"admin_new_invite_label": "Label (e.g. who it is for)",
+	"admin_new_invite_max_uses": "Max uses (empty = unlimited)",
+	"admin_new_invite_prefill_first": "Pre-fill first name (optional)",
+	"admin_new_invite_prefill_last": "Pre-fill last name (optional)",
+	"admin_new_invite_prefill_email": "Pre-fill email (optional)",
+	"admin_new_invite_expires": "Expiry date (optional)",
+	"admin_invite_created_title": "Invite created",
+	"admin_invite_created_desc": "Share this link with the person you are inviting:",
+	"admin_invite_revoke_confirm": "Really revoke this invite?"
 }

frontend/messages/es.json

@@ -640,5 +640,53 @@
 	"filter_operator_and": "Y",
 	"filter_operator_or": "O",
 	"filter_operator_and_label": "Todas las etiquetas seleccionadas deben coincidir (Y)",
-	"filter_operator_or_label": "Al menos una etiqueta debe coincidir (O)"
+	"filter_operator_or_label": "Al menos una etiqueta debe coincidir (O)",
+	"error_invite_not_found": "Enlace de invitación no encontrado o inválido.",
+	"error_invite_exhausted": "Este enlace de invitación ya ha sido completamente utilizado.",
+	"error_invite_revoked": "Este enlace de invitación ha sido desactivado.",
+	"error_invite_expired": "Este enlace de invitación ha expirado.",
+	"register_heading": "Crear cuenta",
+	"register_subtext": "Has sido invitado a unirte al Familienarchiv.",
+	"register_label_first_name": "Nombre",
+	"register_label_last_name": "Apellido",
+	"register_label_email": "Correo electrónico",
+	"register_label_password": "Contraseña",
+	"register_prefill_hint": "Completado automáticamente desde tu invitación – puedes cambiarlo",
+	"register_password_show": "Mostrar contraseña",
+	"register_password_hide": "Ocultar contraseña",
+	"register_btn_submit": "Crear cuenta",
+	"register_invalid_code": "Enlace de invitación inválido",
+	"register_invalid_code_desc": "Este enlace de invitación no es válido, ya ha sido utilizado o ha expirado. Contacta al administrador.",
+	"register_success": "Tu cuenta ha sido creada. Ahora puedes iniciar sesión.",
+	"login_registered_success": "Tu cuenta fue creada con éxito. Inicia sesión ahora.",
+	"admin_tab_invites": "Invitaciones",
+	"admin_invites_list_title": "Invitaciones",
+	"admin_invites_empty": "No hay invitaciones activas.",
+	"admin_btn_new_invite": "Nueva invitación",
+	"admin_btn_show_all": "Mostrar todo",
+	"admin_btn_show_active": "Solo activas",
+	"admin_btn_revoke": "Revocar",
+	"admin_btn_copy_link": "Copiar enlace",
+	"admin_btn_copied": "¡Copiado!",
+	"admin_invite_status_active": "Activa",
+	"admin_invite_status_exhausted": "Agotada",
+	"admin_invite_status_revoked": "Revocada",
+	"admin_invite_status_expired": "Expirada",
+	"admin_invite_col_code": "Código",
+	"admin_invite_col_label": "Etiqueta",
+	"admin_invite_col_uses": "Usos",
+	"admin_invite_col_expiry": "Vencimiento",
+	"admin_invite_col_status": "Estado",
+	"admin_invite_col_link": "Enlace",
+	"admin_invite_unlimited": "∞",
+	"admin_invite_no_expiry": "Sin vencimiento",
+	"admin_new_invite_label": "Etiqueta (p. ej. para quién)",
+	"admin_new_invite_max_uses": "Usos máx. (vacío = ilimitado)",
+	"admin_new_invite_prefill_first": "Prellenar nombre (opcional)",
+	"admin_new_invite_prefill_last": "Prellenar apellido (opcional)",
+	"admin_new_invite_prefill_email": "Prellenar correo (opcional)",
+	"admin_new_invite_expires": "Fecha de vencimiento (opcional)",
+	"admin_invite_created_title": "Invitación creada",
+	"admin_invite_created_desc": "Comparte este enlace con la persona invitada:",
+	"admin_invite_revoke_confirm": "¿Realmente revocar esta invitación?"
 }