feat(fonts): scale up Petaluma maj7 triangle glyph to match NotoSansSymbols2

The chordSymbolMajorSeventh glyph (U+E0BD → U+25B3) in Petaluma was
noticeably smaller than the triangle used by GrigsonSans/Serif. The
GrigsonPetaluma preprocessing step now measures both glyphs and applies
a uniform scale (≈2.3×) so all three typefaces present the △ at the
same visual size.

Author: nelstrom