feat(FR-434): support math in model card.

[agatha197]

resolves #3066 (FR-434 / parent: FR-432)

Added support for LaTeX math expressions and GitHub Flavored Markdown (GFM) in chat messages by integrating KaTeX, remark-gfm, and remark-math plugins into the markdown renderer.

How to test:
Use deepseek model in dogbowl and verify:

1. LaTeX math expressions render correctly (both inline and block)
2. GFM features work (tables, strikethrough, task lists, etc.)

Screenshots:
Result of

$$Euler’s identity $e^{i\pi}+1=0$ is a beautiful formula in $\mathbb{R}^2$. $$ \frac {\partial^r} {\partial \omega^r} \left(\frac {y^{\omega}} {\omega}\right) = \left(\frac {y^{\omega}} {\omega}\right) \left\{(\log y)^r + \sum_{i=1}^r \frac {(-1)^ Ir \cdots (r-i+1) (\log y)^{ri}} {\omega^i} \right\} $$$$

Checklist:

• Documentation
• Test case(s) to demonstrate the difference of before/after

[agatha197]

• feat(FR-433): wrap customTags contents with Collapse #3073
• feat(FR-434): support math in model card. #3067 👈 (View in Graphite)
• main

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Coverage report for ./react

St.❔	Category	Percentage	Covered / Total
🔴	Statements	4.9%	398/8116
🔴	Branches	4.24%	239/5635
🔴	Functions	2.95%	78/2643
🔴	Lines	4.82%	383/7941

Test suite run success

124 tests passing in 14 suites.

Report generated by 🧪jest coverage report action from 445dd03