Rename package and address warnings

Sources/SwiftUIMath/MathBundle/MTFontV2.swift

@@ -0,0 +1,68 @@
+//
+//  MTFontV2.swift
+//
+//
+//  Created by Peter Tang on 15/9/2023.
+//
+
+import Foundation
+import CoreGraphics
+import CoreText
+
+extension MathFont {
+    public func mtfont(size: CGFloat) -> MTFontV2 {
+        MTFontV2(font: self, size: size)
+    }
+}
+public final class MTFontV2: MTFont {
+    let font: MathFont
+    let size: CGFloat
+    private let _cgFont: CGFont
+    private let _ctFont: CTFont
+    private let unitsPerEm: UInt
+    private var _mathTab: MTFontMathTableV2?
+    init(font: MathFont = .latinModernFont, size: CGFloat) {
+        self.font = font
+        self.size = size
+        // MathFont cgfont and ctfont are fast & threadsafe, keep a local copy is cheaper than
+        // handling via NSLock
+        self._cgFont = font.cgFont()
+        self._ctFont = font.ctFont(withSize: size)
+        self.unitsPerEm = self._ctFont.unitsPerEm
+        super.init()
+        
+        super.defaultCGFont = nil
+        super.ctFont = nil
+        super.mathTable = nil
+        super.rawMathTable = nil
+    }
+    override var defaultCGFont: CGFont! {
+        set { fatalError("\(#function): change to \(font.fontName) not allowed.") }
+        get { _cgFont }
+    }
+    override var ctFont: CTFont! {
+        set { fatalError("\(#function): change to \(font.fontName) not allowed.") }
+        get { _ctFont }
+    }
+    private let mtfontV2LockOnMathTable = NSLock()
+    override var mathTable: MTFontMathTable? {
+        set { fatalError("\(#function): change to \(font.rawValue) not allowed.") }
+        get {
+            guard _mathTab == nil else { return _mathTab }
+            //Note: lazy _mathTab initialization is now threadsafe.
+            mtfontV2LockOnMathTable.lock()
+            defer { mtfontV2LockOnMathTable.unlock() }
+            if _mathTab == nil {
+                _mathTab = MTFontMathTableV2(mathFont: font, size: size, unitsPerEm: unitsPerEm)
+            }
+            return _mathTab
+        }
+    }
+    override var rawMathTable: NSDictionary? {
+        set { fatalError("\(#function): change to \(font.rawValue) not allowed.") }
+        get { fatalError("\(#function): access to \(font.rawValue) not allowed.") }
+    }
+    public override func copy(withSize size: CGFloat) -> MTFont {
+        MTFontV2(font: font, size: size)
+    }
+}