Add inspect window showing talent summary and gear for inspected players

Store inspect results (talent points, dual-spec state, gear entries) in a
new InspectResult struct instead of discarding them as chat messages.
Open the inspect window automatically from all Inspect menu items and /inspect.

include/ui/game_screen.hpp

@@ -364,6 +364,10 @@ private:
     bool  showGmTicketWindow_ = false;
     char  gmTicketBuf_[2048] = {};
     void  renderGmTicketWindow(game::GameHandler& gameHandler);
+
+    // Inspect window
+    bool  showInspectWindow_ = false;
+    void  renderInspectWindow(game::GameHandler& gameHandler);
     uint8_t lfgRoles_ = 0x08;  // default: DPS (0x02=tank, 0x04=healer, 0x08=dps)
     uint32_t lfgSelectedDungeon_ = 861;  // default: random dungeon (entry 861 = Random Dungeon WotLK)