Fix camera orbit, deselect, chat formatting, loot/vendor bugs, critter hostility, and character screen

Smooth idle camera orbit without jump at loop boundary, click empty space to
deselect target, auto-target when attacked, fix critter hostility so neutral
factions aren't flagged red, add armor/stats to item templates, fix loot
iterator invalidation, show item template names as fallback, position drop
confirmation at cursor, remove [SYSTEM] chat prefix, show NPC names in monster
say/yell, and prevent auto-login on character select screen.

include/ui/inventory_screen.hpp

@@ -126,6 +126,11 @@ private:
     game::EquipSlot getEquipSlotForType(uint8_t inventoryType, game::Inventory& inv);
     void renderHeldItem();
 
+    // Drop confirmation
+    bool dropConfirmOpen_ = false;
+    int dropBackpackIndex_ = -1;
+    std::string dropItemName_;
+
 public:
     static ImVec4 getQualityColor(game::ItemQuality quality);
 };