Dollar amounts like $50 were incorrectly rendered as LaTeX inline math. Added escaping of $ followed by a digit to $ before markdown parsing, so the markdown parser treats them as literal text instead of math delimiters. Real LaTeX like $x^2$ is unaffected.

Issue for this PR

Closes #30712

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

When text contains dollar amounts (e.g. "$80 + $50 = $130"), the markdown parser's marked-katex-extension interprets $...$ pairs as inline LaTeX math, causing random text fragments to render in a math font.

This PR escapes $ followed by a digit as the HTML entity $ before markdown parsing, preventing the math parser from recognizing it as a delimiter. Real LaTeX like $x^2 + y^2$ or display math $$...$$ is unaffected because the $ is followed by a letter or backslash, not a digit.

Changes in packages/ui/src/context/marked.tsx:

• renderMathInText: escape $ before inline math regex runs
• jsParser path: wrap the return to escape $ before passing to parser

How did you verify your code works?

• Ran all 27 existing UI tests — all pass
• Tested locally with bun dev serve + bun run --cwd packages/app dev
• Verified dollar amounts like "$800 + $400 + $200 = $1400" render as plain text
• Verified real LaTeX like "$E = mc^2$" and "$$\int_0^\infty e^{-x} dx = 1$$" still render as math

Screenshots / recordings

Before (dollar amounts incorrectly rendered as LaTeX math):

After (dollar amounts render as plain text):

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR