Fix inline mode rendering for large operators and fractions

This commit addresses three issues with math rendering:

  1. Large operator limits positioning (continued from previous commit)
  Modified makeLargeOp() and addLimitsToDisplay() to show limits above/below
  in both display and text (inline) modes:
    - Changed: op.limits && style == .display
    - To: op.limits && (style == .display || style == .text)

  This enables operators like \lim, \sum, and \prod to show subscripts/
  superscripts above and below even in inline mode \(...\), not just in
  display mode \[...\].

  2. Fraction font size issue
  Fixed fractions appearing too small in inline mode. Previously, fractions
  used one style level smaller than their parent (standard LaTeX behavior):
    - Display mode → fractions use text style (acceptable)
    - Text mode →

  Root cause:
  Inline delimiters \(...\) insert \textstyle, forcing text mode. In text
  mode, fractionStyle() returned style.inc(), making numerator/denominator
  use script style (two levels smaller than display). This made fraction
  numbers tiny compared to surrounding text in expressions like:
    \(\frac{a}{b} = c\) - a, b were script-sized while c was text-sized

  Solution:
  Modified fractionStyle() to return the SAME style instead of incrementing:
    func fractionStyle() -> MTLineStyle {
        return style  // Was: return style.inc()
    }

  This keeps fraction numerators/denominators at the same font size as
  regular text, preventing them from becoming too small. Spacing and
  positioning (numeratorShiftUp, etc.) still vary by parent style.

  3. Non-regression fixes
  Updated test expectations to match new fraction sizing behavior

Sources/SwiftMath/MathRender/MTMathListBuilder.swift

@@ -271,7 +271,11 @@ public struct MTMathListBuilder {
             return nil
         }
 
-        // Optionally: Add style hint for inline mode
+        // Note: For inline mode, we insert \textstyle to match LaTeX behavior.
+        // However, fractionStyle() has been modified to keep fractions at the
+        // same font size in both display and text modes (not one level smaller).
+        // Large operators show limits above/below in text style due to the updated
+        // condition in makeLargeOp() that checks both .display and .text styles.
         if mode == .inline && list != nil && !list!.atoms.isEmpty {
             // Prepend \textstyle to force inline rendering
             let styleAtom = MTMathStyle(style: .text)

Sources/SwiftMath/MathRender/MTTypesetter.swift

@@ -1726,10 +1726,11 @@ class MTTypesetter {
     }
     
     func fractionStyle() -> MTLineStyle {
-        if style == .scriptOfScript {
-            return .scriptOfScript
-        }
-        return style.inc()
+        // Keep fractions at the same style level instead of incrementing.
+        // This ensures that fraction numerators/denominators have the same
+        // font size as regular text, preventing them from appearing too small
+        // in inline mode or when nested.
+        return style
     }
     
     func makeFraction(_ frac:MTFraction?) -> MTDisplay? {
@@ -2041,7 +2042,9 @@ class MTTypesetter {
     // MARK: - Large Operators
     
     func makeLargeOp(_ op:MTLargeOperator!) -> MTDisplay?  {
-        let limits = op.limits && style == .display
+        // Show limits above/below in both display and text (inline) modes
+        // Only show limits to the side in script modes to keep them compact
+        let limits = op.limits && (style == .display || style == .text)
         var delta = CGFloat(0)
         if op.nucleus.count == 1 {
             var glyph = self.findGlyphForCharacterAtIndex(op.nucleus.startIndex, inString:op.nucleus)
@@ -2086,7 +2089,8 @@ class MTTypesetter {
             currentPosition.x += display!.width
             return display;
         }
-        if op.limits && style == .display {
+        // Show limits above/below in both display and text (inline) modes
+        if op.limits && (style == .display || style == .text) {
             // make limits
             var superScript:MTMathListDisplay? = nil, subScript:MTMathListDisplay? = nil
             if op.superScript != nil {