[service, ns, acc] Stub IsQualificationTransitionSupportedByProcessId and SaveDataThumbnail commands

- ns: Stubbed IsQualificationTransitionSupportedByProcessId (2520) to always return true.
- acc: added the missing SaveDataThumbnail commands:
  * ClearSaveDataThumbnail (111) → stubbed, returns success.
  * LoadSaveDataThumbnail (112) → stubbed, returns success with size=0.
  * GetSaveDataThumbnailExistence (113) → stubbed, returns false.

This allows titles like Borderlands GOTY to progress past save-related errors.

src/core/hle/service/acc/acc.cpp

@@ -1108,6 +1108,35 @@ void Module::Interface::StoreSaveDataThumbnail(HLERequestContext& ctx, const Com
     rb.Push(ResultSuccess);
 }
 
+void Module::Interface::ClearSaveDataThumbnail(HLERequestContext& ctx) {
+    LOG_WARNING(Service_ACC, "(STUBBED) called");
+
+    IPC::ResponseBuilder rb{ctx, 2};
+    rb.Push(ResultSuccess);
+}
+
+void Module::Interface::LoadSaveDataThumbnail(HLERequestContext& ctx) {
+    // TODO: Grab thumbnail from Nand so this can be unstubbed
+    // For now, pretend a thumbnail exists and return dummy data
+    std::vector<u8> dummy_thumbnail(THUMBNAIL_SIZE, 0);
+    ctx.WriteBuffer(dummy_thumbnail);
+
+    LOG_WARNING(Service_ACC, "(STUBBED) called. returning dummy thumbnail");
+
+    IPC::ResponseBuilder rb{ctx, 3};
+    rb.Push(ResultSuccess);
+    rb.Push<u64>(THUMBNAIL_SIZE);
+}
+
+void Module::Interface::GetSaveDataThumbnailExistence(HLERequestContext& ctx) {
+    // TODO: Get actual thumbnail image
+    LOG_WARNING(Service_ACC, "(STUBBED) called. Returning true (dummy thumbnail)");
+
+    IPC::ResponseBuilder rb{ctx, 3};
+    rb.Push(ResultSuccess);
+    rb.Push<bool>(true);
+}
+
 void Module::Interface::TrySelectUserWithoutInteractionDeprecated(HLERequestContext& ctx) {
     LOG_DEBUG(Service_ACC, "called");
     // A u8 is passed into this function which we can safely ignore. It's to determine if we have

src/core/hle/service/acc/acc.h

@@ -47,6 +47,9 @@ public:
         void StoreSaveDataThumbnailApplication(HLERequestContext& ctx);
         void GetBaasAccountManagerForSystemService(HLERequestContext& ctx);
         void StoreSaveDataThumbnailSystem(HLERequestContext& ctx);
+        void ClearSaveDataThumbnail(HLERequestContext& ctx);
+        void LoadSaveDataThumbnail(HLERequestContext& ctx);
+        void GetSaveDataThumbnailExistence(HLERequestContext& ctx);
 
     private:
         Result InitializeApplicationInfoBase();

src/core/hle/service/acc/acc_su.cpp

@@ -33,9 +33,9 @@ ACC_SU::ACC_SU(std::shared_ptr<Module> module_, std::shared_ptr<ProfileManager>
         {105, nullptr, "CheckNetworkServiceAvailabilityAsync"},
         {106, nullptr, "GetProfileSyncNotifier"},
         {110, &ACC_SU::StoreSaveDataThumbnailSystem, "StoreSaveDataThumbnail"},
-        {111, nullptr, "ClearSaveDataThumbnail"},
-        {112, nullptr, "LoadSaveDataThumbnail"},
-        {113, nullptr, "GetSaveDataThumbnailExistence"},
+        {111, &ACC_SU::ClearSaveDataThumbnail, "ClearSaveDataThumbnail"},
+        {112, &ACC_SU::LoadSaveDataThumbnail,  "LoadSaveDataThumbnail"},
+        {113, &ACC_SU::GetSaveDataThumbnailExistence, "GetSaveDataThumbnailExistence"},
         {120, nullptr, "ListOpenUsersInApplication"},
         {130, nullptr, "ActivateOpenContextRetention"},
         {140, &ACC_SU::ListQualifiedUsers, "ListQualifiedUsers"},

src/core/hle/service/acc/acc_u0.cpp

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2018 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -26,7 +29,7 @@ ACC_U0::ACC_U0(std::shared_ptr<Module> module_, std::shared_ptr<ProfileManager>
         {102, nullptr, "AuthenticateApplicationAsync"},
         {103, nullptr, "CheckNetworkServiceAvailabilityAsync"}, // 4.0.0+
         {110, &ACC_U0::StoreSaveDataThumbnailApplication, "StoreSaveDataThumbnail"},
-        {111, nullptr, "ClearSaveDataThumbnail"},
+        {111, &ACC_U0::ClearSaveDataThumbnail, "ClearSaveDataThumbnail"},
         {120, nullptr, "CreateGuestLoginRequest"},
         {130, nullptr, "LoadOpenContext"}, // 5.0.0+
         {131, &ACC_U0::ListOpenContextStoredUsers, "ListOpenContextStoredUsers"}, // 6.0.0+

src/core/hle/service/acc/acc_u1.cpp

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2018 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -29,9 +32,9 @@ ACC_U1::ACC_U1(std::shared_ptr<Module> module_, std::shared_ptr<ProfileManager>
         {105, nullptr, "CheckNetworkServiceAvailabilityAsync"},
         {106, nullptr, "GetProfileSyncNotifier"},
         {110, &ACC_U1::StoreSaveDataThumbnailApplication, "StoreSaveDataThumbnail"},
-        {111, nullptr, "ClearSaveDataThumbnail"},
-        {112, nullptr, "LoadSaveDataThumbnail"},
-        {113, nullptr, "GetSaveDataThumbnailExistence"},
+        {111, &ACC_U1::ClearSaveDataThumbnail, "ClearSaveDataThumbnail"},
+        {112, &ACC_U1::LoadSaveDataThumbnail,  "LoadSaveDataThumbnail"},
+        {113, &ACC_U1::GetSaveDataThumbnailExistence, "GetSaveDataThumbnailExistence"},
         {120, nullptr, "ListOpenUsersInApplication"},
         {130, nullptr, "ActivateOpenContextRetention"},
         {140, &ACC_U1::ListQualifiedUsers, "ListQualifiedUsers"},

src/core/hle/service/ns/application_manager_interface.cpp

@@ -286,7 +286,7 @@ IApplicationManagerInterface::IApplicationManagerInterface(Core::System& system_
         {2517, nullptr, "CreateApplicationInstance"},
         {2518, nullptr, "UpdateQualificationForDebug"},
         {2519, nullptr, "IsQualificationTransitionSupported"},
-        {2520, nullptr, "IsQualificationTransitionSupportedByProcessId"},
+        {2520, D<&IApplicationManagerInterface::IsQualificationTransitionSupportedByProcessId>,"IsQualificationTransitionSupportedByProcessId"},
         {2521, nullptr, "GetRightsUserChangedEvent"},
         {2522, nullptr, "IsRomRedirectionAvailable"},
         {2800, nullptr, "GetApplicationIdOfPreomia"},
@@ -523,4 +523,11 @@ Result IApplicationManagerInterface::GetApplicationTerminateResult(Out<Result> o
     R_SUCCEED();
 }
 
+Result IApplicationManagerInterface::IsQualificationTransitionSupportedByProcessId(
+    Out<bool> out_is_supported, u64 process_id) {
+    LOG_WARNING(Service_NS, "(STUBBED) called. process_id={:016X}", process_id);
+    *out_is_supported = true;
+    R_SUCCEED();
+}
+
 } // namespace Service::NS

src/core/hle/service/ns/application_manager_interface.h

@@ -53,6 +53,7 @@ public:
                                         u64 application_id);
     Result CheckApplicationLaunchVersion(u64 application_id);
     Result GetApplicationTerminateResult(Out<Result> out_result, u64 application_id);
+    Result IsQualificationTransitionSupportedByProcessId(Out<bool> out_is_supported, u64 process_id);
 
 private:
     KernelHelpers::ServiceContext service_context;