Add cookie_policy_url field to cookie banners

Introduce a required cookie_policy_url alongside the existing
privacy_policy_url (now optional) so banners can link directly to a
dedicated cookie policy — a compliance best practice recommended by
CNIL, ICO, and the EDPB. Existing rows are seeded from their current
privacy_policy_url value.

Both {{cookie_policy_link}} and {{privacy_policy_link}} placeholders
are supported independently in banner description translations.

Signed-off-by: Émile Ré <emile@getprobo.com>

pkg/server/api/console/v1/graphql/cookie_banner.graphql

@@ -81,7 +81,8 @@ type CookieBanner implements Node {
     name: String!
     origin: String!
     state: CookieBannerState!
-    privacyPolicyUrl: String!
+    privacyPolicyUrl: String
+    cookiePolicyUrl: String!
     consentExpiryDays: Int!
     consentMode: CookieConsentMode!
     showBranding: Boolean!
@@ -266,7 +267,8 @@ input CreateCookieBannerInput {
     organizationId: ID!
     name: String!
     origin: String!
-    privacyPolicyUrl: String!
+    privacyPolicyUrl: String
+    cookiePolicyUrl: String!
     consentExpiryDays: Int!
     consentMode: CookieConsentMode!
 }
@@ -275,6 +277,7 @@ input UpdateCookieBannerInput {
     cookieBannerId: ID!
     name: String
     privacyPolicyUrl: String
+    cookiePolicyUrl: String
     consentExpiryDays: Int
     consentMode: CookieConsentMode
     defaultLanguage: String