feat(webapp): expose LAVA settings in admin UI and demo

Add RU/EN admin locale strings for the LAVA settings subsection and
field labels, regenerate the demo settings manifest snapshot, and list
LAVA among the demo dataset payment methods.

locales/en.json

@@ -1220,6 +1220,7 @@
   "admin_settings_subsection_wata": "Wata",
   "admin_settings_subsection_heleket": "Heleket",
   "admin_settings_subsection_paykilla": "PayKilla",
+  "admin_settings_subsection_lava": "LAVA",
   "admin_settings_provider_webhook_url": "Webhook URL",
   "admin_settings_provider_webhook_url_hint": "Use this URL in the provider webhook settings.",
   "admin_settings_panel_webhook_url_hint": "Use this URL as WEBHOOK_URL in Remnawave Panel.",
@@ -1772,6 +1773,18 @@
   "admin_settings_field_severpay_return_url_label": "SeverPay Return URL",
   "admin_settings_field_severpay_lifetime_minutes_label": "SeverPay Lifetime Minutes",
   "admin_settings_field_severpay_lifetime_minutes_description": "Controls the 'SeverPay Lifetime Minutes' setting in admin overrides.",
+  "admin_settings_field_lava_enabled_label": "Enabled",
+  "admin_settings_field_lava_shop_id_label": "Shop ID",
+  "admin_settings_field_lava_secret_key_label": "Secret key",
+  "admin_settings_field_lava_secret_key_description": "Signs outgoing API requests (HMAC-SHA256 in the Signature header).",
+  "admin_settings_field_lava_webhook_secret_label": "Webhook secret",
+  "admin_settings_field_lava_webhook_secret_description": "The shop's additional key used to verify webhook signatures. Leave empty to reuse the secret key.",
+  "admin_settings_field_lava_base_url_label": "Base URL",
+  "admin_settings_field_lava_return_url_label": "Return URL",
+  "admin_settings_field_lava_lifetime_minutes_label": "Payment link lifetime (minutes)",
+  "admin_settings_field_lava_lifetime_minutes_description": "1..7200; leave empty for the LAVA default.",
+  "admin_settings_field_lava_include_services_label": "Payment services filter",
+  "admin_settings_field_lava_include_services_description": "Comma-separated LAVA pay services shown on the payment page (e.g. card,sbp). Empty shows everything enabled for the shop.",
   "admin_settings_field_cryptopay_enabled_label": "CryptoPay Enabled",
   "admin_settings_field_cryptopay_token_label": "CryptoPay Token",
   "admin_settings_field_cryptopay_network_label": "CryptoPay Network",

locales/ru.json

@@ -1220,6 +1220,7 @@
   "admin_settings_subsection_wata": "Wata",
   "admin_settings_subsection_heleket": "Heleket",
   "admin_settings_subsection_paykilla": "PayKilla",
+  "admin_settings_subsection_lava": "LAVA",
   "admin_settings_provider_webhook_url": "Webhook URL",
   "admin_settings_provider_webhook_url_hint": "Укажите этот адрес в настройках вебхуков провайдера.",
   "admin_settings_panel_webhook_url_hint": "Укажите этот адрес как WEBHOOK_URL в Remnawave Panel.",
@@ -1772,6 +1773,18 @@
   "admin_settings_field_severpay_return_url_label": "Return URL",
   "admin_settings_field_severpay_lifetime_minutes_label": "Срок жизни ссылки (мин)",
   "admin_settings_field_severpay_lifetime_minutes_description": "30..4320; пусто — значение провайдера",
+  "admin_settings_field_lava_enabled_label": "Включена",
+  "admin_settings_field_lava_shop_id_label": "Shop ID",
+  "admin_settings_field_lava_secret_key_label": "Секретный ключ",
+  "admin_settings_field_lava_secret_key_description": "Подписывает исходящие запросы к API (HMAC-SHA256 в заголовке Signature).",
+  "admin_settings_field_lava_webhook_secret_label": "Ключ вебхуков",
+  "admin_settings_field_lava_webhook_secret_description": "Дополнительный ключ магазина для проверки подписи вебхуков. Пусто — используется секретный ключ.",
+  "admin_settings_field_lava_base_url_label": "Base URL",
+  "admin_settings_field_lava_return_url_label": "Return URL",
+  "admin_settings_field_lava_lifetime_minutes_label": "Срок жизни ссылки (мин)",
+  "admin_settings_field_lava_lifetime_minutes_description": "1..7200; пусто — значение провайдера",
+  "admin_settings_field_lava_include_services_label": "Фильтр способов оплаты",
+  "admin_settings_field_lava_include_services_description": "Через запятую: способы оплаты LAVA на странице счёта (например card,sbp). Пусто — все доступные магазину.",
   "admin_settings_field_cryptopay_enabled_label": "Включена",
   "admin_settings_field_cryptopay_token_label": "Token",
   "admin_settings_field_cryptopay_network_label": "Network",