🎨 Palette: Add tooltips for financial parameters

[aarjava]

💡 What: Added explanatory tooltips to "High Volatility Quantile" and "Transaction Cost (bps)" inputs in the sidebar.
🎯 Why: Users often struggle with financial jargon like "basis points" or statistical terms like "quantiles". Providing concrete examples reduces cognitive load.
♿ Accessibility: Reduces the need for external reference and prevents input errors.
Dependencies: Added matplotlib to requirements.txt to fix runtime crash.

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PR created automatically by Jules for task 2790775248146513756 started by @aarjava

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