Attach coalesced Buffer if any source Buffer is attached

A buffer that's attached to a context could be coalesced into a larger buffer which isn't attached, this would break as it wouldn't keep the buffer alive till the end of the associated context. To fix this if any source buffers are attached then the resulting coalesced buffer is also attached now.

app/src/main/cpp/skyline/gpu/buffer_manager.h

@@ -62,10 +62,11 @@ namespace skyline::gpu {
         bool try_lock();
 
         /**
+         * @param attachBuffer A function that attaches the buffer to the current context, this'll be called when coalesced buffers are merged into the current buffer
          * @return A pre-existing or newly created Buffer object which covers the supplied mappings
          * @note The buffer manager **must** be locked prior to calling this
          */
-        BufferView FindOrCreate(GuestBuffer guestMapping, ContextTag tag = {});
+        BufferView FindOrCreate(GuestBuffer guestMapping, ContextTag tag = {}, const std::function<void(std::shared_ptr<Buffer>, ContextLock<Buffer> &)> &attachBuffer = {});
 
         /**
          * @return A dynamically allocated megabuffer which can be used to store buffer modifications allowing them to be replayed in-sequence on the GPU