feat: expose libsession's Pro URL registry to Kotlin

library/src/main/cpp/pro_backend.cpp

@@ -4,6 +4,7 @@
 
 #include <oxenc/hex.h>
 #include <session/pro_backend.hpp>
+#include <session/session_protocol.h>
 
 #include "jni_utils.h"
 #include "util.h"
@@ -60,6 +61,28 @@ JavaLocalRef<jobject> serialize_provider_urls(JNIEnv* env, const pb::ProviderURL
                                 jstring_from_optional(env, u.cancel_subscription_url).get())};
 }
 
+/// The Pro URL registry as one Kotlin object. Reads `SESSION_PROTOCOL_STRINGS` directly - it is
+/// declared `extern const` in the public C header, so no C++ surface had to be added for this.
+///
+/// Field order MUST match `ProUrls`'s constructor. The two document urls are the `url_pro_*` ones:
+/// the registry also carries generic `url_privacy_policy` / `url_terms_of_service`, which are
+/// different pages and do not belong on a Pro object.
+JavaLocalRef<jobject> serialize_pro_urls(JNIEnv* env) {
+    static BasicJavaClassInfo cls(env, "network/loki/messenger/libsession_util/pro/ProUrls",
+            "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;"
+            "Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)V");
+    const auto& s = SESSION_PROTOCOL_STRINGS;
+    return {env, env->NewObject(cls.java_class, cls.constructor,
+                                jstring_from_optional(env, std::string_view(s.url_pro_access_not_found)).get(),
+                                jstring_from_optional(env, std::string_view(s.url_pro_faq)).get(),
+                                jstring_from_optional(env, std::string_view(s.url_pro_page)).get(),
+                                jstring_from_optional(env, std::string_view(s.url_pro_privacy_policy)).get(),
+                                jstring_from_optional(env, std::string_view(s.url_pro_roadmap)).get(),
+                                jstring_from_optional(env, std::string_view(s.url_pro_support)).get(),
+                                jstring_from_optional(env, std::string_view(s.url_pro_terms_of_service)).get(),
+                                jstring_from_optional(env, std::string_view(s.url_pro_upgrade)).get())};
+}
+
 // §1: `plan` is a parsed ProPlanPeriod (count + unit). We hand the app the structured pair —
 // count as an int, unit as a lowercase name — so nothing downstream has to re-parse a slug (matching
 // the nodejs glue's {planCount, planUnit}). The unit is preserved exactly, never canonicalized.
@@ -249,6 +272,14 @@ Java_network_loki_messenger_libsession_1util_pro_BackendRequests_providerUrls(
     });
 }
 
+extern "C"
+JNIEXPORT jobject JNICALL
+Java_network_loki_messenger_libsession_1util_pro_BackendRequests_proUrls(JNIEnv* env, jobject) {
+    return run_catching_cxx_exception_or_throws<jobject>(env, [=]() -> jobject {
+        return serialize_pro_urls(env).release();
+    });
+}
+
 // --- Backend identity constants (single source of truth in libsession) ---
 
 extern "C"

library/src/main/java/network/loki/messenger/libsession_util/pro/BackendRequests.kt

@@ -40,6 +40,13 @@ object BackendRequests : LibSessionUtilCApi() {
 
     external fun providerUrls(providerCode: String): ProviderUrls?
 
+    /**
+     * The Pro URL registry. Identical for every user and owned by libsession, so read this rather than
+     * copying the values — a client-side copy of a libsession constant is a value that can silently
+     * drift from the one the other clients use.
+     */
+    external fun proUrls(): ProUrls
+
     /**
      * The purchasable payment-provider slugs to surface to users (single source of truth in libsession;
      * excludes non-purchasable providers like `stf`). Order is not significant — the client

library/src/main/java/network/loki/messenger/libsession_util/pro/ProBackendResponses.kt

@@ -53,6 +53,27 @@ data class ProRequest(
     val body: String,
 )
 
+/**
+ * The Pro URL registry — the `url_pro_*` fields of libsession's `SESSION_PROTOCOL_STRINGS`.
+ *
+ * Not per-provider and not translation data: these are identical for every user, which is why
+ * libsession owns them. Exposed as one object rather than eight calls, matching [ProviderUrls].
+ *
+ * Note [privacyPolicy] and [termsOfService] are the **Pro** documents (`url_pro_*`), not Session's
+ * general ones — the registry carries both pairs and they are different pages.
+ */
+@Keep
+data class ProUrls(
+    val accessNotFound: String,
+    val faq: String,
+    val page: String,
+    val privacyPolicy: String,
+    val roadmap: String,
+    val support: String,
+    val termsOfService: String,
+    val upgrade: String,
+)
+
 /** Per-provider support/management URLs — libsession is the source of truth for these. */
 @Keep
 data class ProviderUrls(