Palette: Add tooltips to complex sidebar inputs

[aarjava]

💡 What: Added help tooltips to 9 complex financial inputs in the sidebar (e.g., Factor Beta Window, ADV Participation %, Volatility Quantiles).
🎯 Why: To clarify technical terms for users and improve accessibility, addressing the "Missing helper text for complex forms" opportunity.
♿ Accessibility: Improves understanding of input constraints and units (e.g., "10 bps = 0.10%").
🔧 Fix: Added matplotlib to requirements.txt to resolve a runtime crash in the "Portfolio" tab caused by missing styling dependencies.
📝 Journal: Added .Jules/palette.md to document UX learnings regarding Streamlit verification.

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PR created automatically by Jules for task 5125782292363453215 started by @aarjava

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