Extended FontWeight and FontStyle Enums

Description

Extends ScintillaTypes.h to include complete DirectWrite font weight and style enums, enabling proper support for all font variants like "Cascadia Mono Light", "Iosevka Oblique", etc.

Issues Addressed

• #4150 - Variable fonts support
• #5455 - Cascadia Mono Light rendering

Changes

FontWeight Enum (Extended)

Original had only: Normal(400), SemiBold(600), Bold(700)

Now includes all DWRITE_FONT_WEIGHT values:

• Thin (100), ExtraLight (200), Light (300), SemiLight (350)
• Normal (400), Medium (500)
• SemiBold (600), Bold (700), ExtraBold (800), Black (900), ExtraBlack (950)

FontStyle Enum (New)

Matches DWRITE_FONT_STYLE:

• Normal (0) - Upright
• Oblique (1) - Mechanically slanted
• Italic (2) - True italic curves

Files Modified

• scintilla/include/ScintillaTypes.h