feat: create the main font structure

Author: helbertgomes

Sources/OpenSwiftUI/Views/Text Input and Output/Setting a font/Font.swift

@@ -0,0 +1,28 @@
+//
+// Font+Design.swift
+// OpenSwiftUI
+//
+// Created by Helbert Gomes on Jan 27, 2026.
+// Licensed under the MIT License. See LICENSE in the project root for license information.
+// SPDX-License-Identifier: MIT
+
+import Foundation
+
+extension Font {
+
+    /// A design to use for fonts.
+    public enum Design : String, Codable, Equatable, Hashable, Sendable {
+
+        /// The default design.
+        case `default`
+
+        /// The serif design.
+        case serif
+
+        /// The rounded design.
+        case rounded
+
+        /// The monospaced design.
+        case monospaced
+    }
+}

Sources/OpenSwiftUI/Views/Text Input and Output/Setting a font/Getting system fonts/Font+Design.swift

@@ -0,0 +1,49 @@
+//
+// Font+TextStyle.swift
+// OpenSwiftUI
+//
+// Created by Helbert Gomes on Jan 27, 2026.
+// Licensed under the MIT License. See LICENSE in the project root for license information.
+// SPDX-License-Identifier: MIT
+
+import Foundation
+
+extension Font {
+
+    /// A dynamic text style to use for fonts.
+    public enum TextStyle : String, Codable, Equatable, Hashable, CaseIterable, Sendable {
+
+        /// The font style for large titles.
+        case largeTitle
+
+        /// The font used for first level hierarchical headings.
+        case title
+
+        /// The font used for second level hierarchical headings.
+        case title2
+
+        /// The font used for third level hierarchical headings.
+        case title3
+
+        /// The font used for headings.
+        case headline
+
+        /// The font used for subheadings.
+        case subheadline
+
+        /// The font used for body text.
+        case body
+
+        /// The font used for callouts.
+        case callout
+
+        /// The font used in footnotes.
+        case footnote
+
+        /// The font used for standard captions.
+        case caption
+
+        /// The font used for alternate captions.
+        case caption2
+    }
+}

Sources/OpenSwiftUI/Views/Text Input and Output/Setting a font/Getting system fonts/Font+TextStyle.swift

@@ -0,0 +1,57 @@
+//
+// Font+Weight.swift
+// OpenSwiftUI
+//
+// Created by Helbert Gomes on Jan 27, 2026.
+// Licensed under the MIT License. See LICENSE in the project root for license information.
+// SPDX-License-Identifier: MIT
+
+import Foundation
+
+extension Font {
+
+    /// A weight to use for fonts.
+    @frozen public struct Weight : Codable, Equatable, Hashable, Sendable {
+
+        // MARK: - Getting font weights
+
+        /// The ultra light weight.
+        public static let ultraLight = Font.Weight(value: -0.8)
+
+        /// The thin weight.
+        public static let thin = Font.Weight(value: -0.6)
+
+        /// The light weight.
+        public static let light = Font.Weight(value: -0.4)
+
+        /// The regular weight.
+        public static let regular = Font.Weight(value: 0)
+
+        /// The medium weight.
+        public static let medium = Font.Weight(value: 0.23)
+
+        /// The semibold weight.
+        public static let semibold = Font.Weight(value: 0.3)
+
+        /// The bold weight.
+        public static let bold = Font.Weight(value: 0.4)
+
+        /// The heavy weight.
+        public static let heavy = Font.Weight(value: 0.56)
+
+        /// The black weight.
+        public static let black = Font.Weight(value: 0.62)
+
+        // MARK: - Creating a font weight
+
+        /// The value of the weight.
+        package let value: Double
+
+        /// Creates a new weight with the given value.
+        /// 
+        /// - Parameter value: The value of the weight.
+        private init(value: Double) {
+            self.value = value
+        }
+    }
+}