fix: animation stutter, resolution crash, memory cap, spell tooltip hints, GO collision

- Animation stutter: skip playAnimation(Run) for the local player in the
  server movement callback — the player renderer state machine already manages
  it; resetting animTime on every movement packet caused visible stutter
- Resolution crash: reorder swapchain recreation so old swapchain is only
  destroyed after confirming the new build succeeded; add null-swapchain
  guard in beginFrame to survive the retry window
- Memory cap: reduce cache budget from 80% uncapped to 50% hard-capped at
  16 GB to prevent excessive RAM use on high-memory systems
- Spell tooltip: suppress "Drag to action bar / Double-click to cast" hints
  when the tooltip is shown from the action bar (showUsageHints=false)
- M2 collision: add watermelon/melon/squash/gourd to foliage (no-collision);
  exclude chair/bench/stool/seat/throne from smallSolidProp so invisible chair
  bounding boxes no longer trap the player

src/rendering/vk_context.cpp

@@ -1051,14 +1051,21 @@ bool VkContext::recreateSwapchain(int width, int height) {
 
     auto swapRet = builder.build();
 
-    if (oldSwapchain) {
-        vkDestroySwapchainKHR(device, oldSwapchain, nullptr);
+    if (!swapRet) {
+        // Destroy old swapchain now that we failed (it can't be used either)
+        if (oldSwapchain) {
+            vkDestroySwapchainKHR(device, oldSwapchain, nullptr);
+            swapchain = VK_NULL_HANDLE;
+        }
+        LOG_ERROR("Failed to recreate swapchain: ", swapRet.error().message());
+        // Keep swapchainDirty=true so the next frame retries
+        swapchainDirty = true;
+        return false;
     }
 
-    if (!swapRet) {
-        LOG_ERROR("Failed to recreate swapchain: ", swapRet.error().message());
-        swapchain = VK_NULL_HANDLE;
-        return false;
+    // Success — safe to retire the old swapchain
+    if (oldSwapchain) {
+        vkDestroySwapchainKHR(device, oldSwapchain, nullptr);
     }
 
     auto vkbSwap = swapRet.value();
@@ -1322,6 +1329,7 @@ bool VkContext::recreateSwapchain(int width, int height) {
 
 VkCommandBuffer VkContext::beginFrame(uint32_t& imageIndex) {
     if (deviceLost_) return VK_NULL_HANDLE;
+    if (swapchain == VK_NULL_HANDLE) return VK_NULL_HANDLE;  // Swapchain lost; recreate pending
 
     auto& frame = frames[currentFrame];