[vk, renderdoc] fixed zero-sized streambuffer bug on old heap-absent GPUs (#4052)

This fix a bug in which eden crashes when renderdoc is attached to vulkan.
that kept me away from renderdoc for around a year now.

the bug:

in video_core\renderer_vulkan\vk_staging_buffer_pool.cpp
in GetStreamBufferSize(...)
if device.HasDebuggingToolAttached()
but heap is empty/unavailable <-- Case in my old nvidia kepler gpu

the original method returns size 0, right?
the change honors same original behavior, while covers my case properly, returning MAX_STREAM_BUFFER_SIZE.

addl some log tip and some minimal doc. fully safe. let it rip.

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4052
Reviewed-by: MaranBr <maranbr@eden-emu.dev>
Reviewed-by: Lizzie <lizzie@eden-emu.dev>

src/video_core/renderer_vulkan/vk_staging_buffer_pool.cpp

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
@@ -31,11 +31,18 @@ constexpr VkDeviceSize MAX_ALIGNMENT = 256;
 constexpr VkDeviceSize MAX_STREAM_BUFFER_SIZE = 128_MiB;
 
 size_t GetStreamBufferSize(const Device& device) {
+    if (!device.HasDebuggingToolAttached()) {
+        return MAX_STREAM_BUFFER_SIZE;
+    }
+
     VkDeviceSize size{0};
-    if (device.HasDebuggingToolAttached()) {
-        ForEachDeviceLocalHostVisibleHeap(device, [&size](size_t index, VkMemoryHeap& heap) {
-            size = (std::max)(size, heap.size);
-        });
+    bool has_device_local_host_visible_heap{};
+    ForEachDeviceLocalHostVisibleHeap(device, [&size, &has_device_local_host_visible_heap](
+                                                  size_t index, VkMemoryHeap& heap) {
+        has_device_local_host_visible_heap = true;
+        size = (std::max)(size, heap.size);
+    });
+    if (has_device_local_host_visible_heap) {
         // If rebar is not supported, cut the max heap size to 40%. This will allow 2 captures to be
         // loaded at the same time in RenderDoc. If rebar is supported, this shouldn't be an issue
         // as the heap will be much larger.

src/video_core/vulkan_common/vulkan_device.cpp

@@ -1481,6 +1481,12 @@ void Device::CollectToolingInfo() {
         has_nsight_graphics = has_nsight_graphics || name == "NVIDIA Nsight Graphics";
         has_radeon_gpu_profiler = has_radeon_gpu_profiler || name == "Radeon GPU Profiler";
     }
+#ifdef _WIN32
+    if (has_renderdoc) {
+        LOG_INFO(Render_Vulkan,
+                 "Windows default RenderDoc output folder: %LOCALAPPDATA%\\Temp\\RenderDoc");
+    }
+#endif
 }
 
 std::vector<VkDeviceQueueCreateInfo> Device::GetDeviceQueueCreateInfos() const {