Fix spell targeting, item query parsing, loot UI, hair/skin textures, and attack animations

Fix spell cast target fallback using selected target instead of no-op tautology.
Fix SMSG_ITEM_QUERY_SINGLE_RESPONSE to always read 10 stat pairs (server sends
all 10 regardless of statsCount), fixing misaligned armor/stat reads. Fix XP gain
parser to read float groupRate + uint8 RAF instead of bogus uint32 groupBonus.
Add item icons and quality-colored names to loot window. Use actual character
appearance bytes for CharSections.dbc skin/face/hair lookups instead of hardcoded
defaults. Add weapon-type-aware attack animation selection (2H prioritizes anim 18).
Add readable spell cast failure messages and vendor sell hint.

include/ui/inventory_screen.hpp

@@ -76,7 +76,9 @@ private:
 
     // Item icon cache: displayInfoId -> GL texture
     std::unordered_map<uint32_t, GLuint> iconCache_;
+public:
     GLuint getItemIcon(uint32_t displayInfoId);
+private:
 
     // Character model preview
     std::unique_ptr<rendering::CharacterPreview> charPreview_;