Do small vector optimization for all communication

I once read years ago somewhere on Stack Overflow that `std::vectors`
with that are preinitialized to a default size would allocate the
initial capacity on the stack. This of course doesn't make any
sense (run time sized stack allocations can cause all kinds of issues),
so we were still allocating with our default 64-byte sized buffers, but
just not as often.

src/wine-host/bridges/vst2.cpp

@@ -179,7 +179,7 @@ Vst2Bridge::Vst2Bridge(MainContext& main_context,
 
     parameters_handler = Win32Thread([&]() {
         sockets.host_vst_parameters.receive_multi<Parameter>(
-            [&](Parameter request, std::vector<uint8_t>& buffer) {
+            [&](Parameter request, SerializationBufferBase& buffer) {
                 // Both `getParameter` and `setParameter` functions are passed
                 // through on this socket since they have a lot of overlap. The
                 // presence of the `value` field tells us which one we're
@@ -216,7 +216,7 @@ Vst2Bridge::Vst2Bridge(MainContext& main_context,
             plugin->numOutputs);
 
         sockets.host_vst_process_replacing.receive_multi<AudioBuffers>(
-            [&](AudioBuffers request, std::vector<uint8_t>& buffer) {
+            [&](AudioBuffers request, SerializationBufferBase& buffer) {
                 // Since the value cannot change during this processing cycle,
                 // we'll send the current transport information as part of the
                 // request so we prefetch it to avoid unnecessary callbacks from