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/toml++/impl/at_path.hpp

@@ -0,0 +1,97 @@
+//# This file is a part of toml++ and is subject to the the terms of the MIT license.
+//# Copyright (c) Mark Gillard <mark.gillard@outlook.com.au>
+//# See https://github.com/marzer/tomlplusplus/blob/master/LICENSE for the full license text.
+// SPDX-License-Identifier: MIT
+#pragma once
+
+#include "forward_declarations.hpp"
+
+/// \cond
+TOML_IMPL_NAMESPACE_START
+{
+	template <typename T>
+	using parse_path_callback = bool(TOML_CALLCONV*)(void*, T);
+
+	TOML_NODISCARD
+	bool TOML_CALLCONV parse_path(std::string_view,
+								  void*,
+								  parse_path_callback<std::string_view>,
+								  parse_path_callback<size_t>);
+}
+TOML_IMPL_NAMESPACE_END;
+/// \endcond
+
+TOML_NAMESPACE_START
+{
+	/// \brief Returns a view of the node matching a fully-qualified "TOML path".
+	///
+	/// \detail \cpp
+	/// auto config = toml::parse(R"(
+	///
+	/// [foo]
+	/// bar = [ 0, 1, 2, [ 3 ], { kek = 4 } ]
+	///
+	/// )"sv);
+	///
+	/// std::cout << toml::at_path(config, "foo.bar[2]") << "\n";
+	/// std::cout << toml::at_path(config, "foo.bar[3][0]") << "\n";
+	/// std::cout << toml::at_path(config, "foo.bar[4].kek") << "\n";
+	/// \ecpp
+	///
+	/// \out
+	/// 2
+	/// 3
+	/// 4
+	/// \eout
+	///
+	///
+	/// \note Keys in paths are interpreted literally, so whitespace (or lack thereof) matters:
+	/// \cpp
+	/// toml::at_path(config, "foo.bar")  // same as config["foo"]["bar"]
+	/// toml::at_path(config, "foo. bar") // same as config["foo"][" bar"]
+	/// toml::at_path(config, "foo..bar") // same as config["foo"][""]["bar"]
+	/// toml::at_path(config, ".foo.bar") // same as config[""]["foo"]["bar"]
+	/// \ecpp
+	/// <br>
+	/// Additionally, TOML allows '.' (period) characters to appear in keys if they are quoted strings.
+	/// This function makes no allowance for this, instead treating all period characters as sub-table delimiters.
+	/// If you have periods in your table keys, first consider:
+	/// 1. Not doing that
+	/// 2. Using node_view::operator[] instead.
+	///
+	/// \param root		The root node from which the path will be traversed.
+	/// \param path		The "TOML path" to traverse.
+	TOML_NODISCARD
+	TOML_EXPORTED_FREE_FUNCTION
+	node_view<node> TOML_CALLCONV at_path(node & root, std::string_view path) noexcept;
+
+	/// \brief Returns a const view of the node matching a fully-qualified "TOML path".
+	///
+	/// \see #toml::at_path(node&, std::string_view)
+	TOML_NODISCARD
+	TOML_EXPORTED_FREE_FUNCTION
+	node_view<const node> TOML_CALLCONV at_path(const node& root, std::string_view path) noexcept;
+
+#if TOML_ENABLE_WINDOWS_COMPAT
+
+	/// \brief Returns a view of the node matching a fully-qualified "TOML path".
+	///
+	/// \availability This overload is only available when #TOML_ENABLE_WINDOWS_COMPAT is enabled.
+	///
+	/// \see #toml::at_path(node&, std::string_view)
+	TOML_NODISCARD
+	TOML_EXPORTED_FREE_FUNCTION
+	node_view<node> TOML_CALLCONV at_path(node & root, std::wstring_view path);
+
+	/// \brief Returns a const view of the node matching a fully-qualified "TOML path".
+	///
+	/// \availability This overload is only available when #TOML_ENABLE_WINDOWS_COMPAT is enabled.
+	///
+	/// \see #toml::at_path(node&, std::string_view)
+	TOML_NODISCARD
+	TOML_EXPORTED_FREE_FUNCTION
+	node_view<const node> TOML_CALLCONV at_path(const node& root, std::wstring_view path);
+
+#endif
+}
+TOML_NAMESPACE_END;