feature: hud (#37)

* build: replace FetchContent with direct includes for glm

* build(deps): replace SOIL2 with stb for image and vorbis decoding

* build: replace FetchContent with direct includes for toml++

* refactor(texture): bump block texture size to 512 and disable items tab

* feat: add hotbar system with ItemStack and RowLayout

* fix(ui): restrict Ctrl key handling to typing mode

* feat(ui): add widget border support and highlight selected hotbar slot

* fix(ui): update borders on scale change and correct Image width

- Added update_border() calls in set_scale() for Button, ChatBox, Image, Label, and TextField.
- Fixed Image::width() to multiply by width instead of height.
- Added early return in Widget::update_border() if border is not supported.

* feat(ui): add border visual feedback on slider drag

* feat(ui): add ItemSlot widget and refactor hotbar to use it

* feat(world_scene): add inventory UI and pause type enum

* feat(ui): add item slot tooltip and make window size static

* fix(ui label): account for background offset in width/height

* refactor(ui): centralize item info label in inventory and add update

* feat(ui): add hotbar interaction in inventory UI

* fix(inventory-ui): correct row creation logic for first item

The loop starting at index 0 created a new row on the first iteration
(i % 10 == 0). Shift the loop to start at 1 and adjust modulus condition
to create rows correctly every 10 items.

* feat(block): add name_key for localized block names

Add `name_key` field to all block TOML definitions, enabling per-block localization. Update `BlockData` struct and `BlockManager` with `local_name()` method that returns a localized string via the translation system. Add corresponding entries to `en_US.json` and `zh_CN.json`. Modify inventory UI to use the localized name when displaying block info, and fix a bug where emptying a hotbar slot did not clear the item locally.

* fix(ui): change inventory item slot color from white to gray

* fix(ui): add missing include for std::array

include/glm/ext/quaternion_trigonometric.inl

@@ -0,0 +1,37 @@
+#include "scalar_constants.hpp"
+
+namespace glm
+{
+	template<typename T, qualifier Q>
+	GLM_FUNC_QUALIFIER T angle(qua<T, Q> const& x)
+	{
+		if (abs(x.w) > cos_one_over_two<T>())
+		{
+			T const a = asin(sqrt(x.x * x.x + x.y * x.y + x.z * x.z)) * static_cast<T>(2);
+			if(x.w < static_cast<T>(0))
+				return pi<T>() * static_cast<T>(2) - a;
+			return a;
+		}
+
+		return acos(x.w) * static_cast<T>(2);
+	}
+
+	template<typename T, qualifier Q>
+	GLM_FUNC_QUALIFIER vec<3, T, Q> axis(qua<T, Q> const& x)
+	{
+		T const tmp1 = static_cast<T>(1) - x.w * x.w;
+		if(tmp1 <= static_cast<T>(0))
+			return vec<3, T, Q>(0, 0, 1);
+		T const tmp2 = static_cast<T>(1) / sqrt(tmp1);
+		return vec<3, T, Q>(x.x * tmp2, x.y * tmp2, x.z * tmp2);
+	}
+
+	template<typename T, qualifier Q>
+	GLM_FUNC_QUALIFIER qua<T, Q> angleAxis(T const& angle, vec<3, T, Q> const& v)
+	{
+		T const a(angle);
+		T const s = glm::sin(a * static_cast<T>(0.5));
+
+		return qua<T, Q>(glm::cos(a * static_cast<T>(0.5)), v * s);
+	}
+}//namespace glm