Created a new Smart Stats widget to Overview tab that calculates your Daily Average spending and projects your End Of Month spending based on your current Daily Average spending. Then after that, I looked through every file and did some refactors, bug fixes & UI polishing (especially on mobile).

Bug fixes:

• Excluded “Starting Balance” transactions from calculateIncome & getMonthlyTrends so adding an account with starting balance doesn’t inflate income stats or trend charts.
• Fixed deleteCategory to clean up everything (including transaction splits, auto-categorization rules and category customization).
• Added a transfer account validation to Add Transaction dialog to prevent saving a transfer with empty “From/To” accounts or transferring money to the same account.
• Fixed the “Will exceed budget” warning showing when adding Income.
• Added defaultAccountId to JSON export/import handlers so the user’s default account setting survives JSON backups.

Refactors:

• Extracted the duplicated color/icon Popover UI from settingsUI & accountManager in to a single colorIconPicker component.
• Extracted duplicated Recharts tooltip styling into a shared chartStyles.ts constant.

UI Polish:

• Made the calendar mobile-friendly by showing colored dots on small screens and full text & balances on larger ones.
• Hid the default calendar navigation arrows that appeared at the top of the screen and adjusted button heights to match.
• Adjusted TabsList to use text-xs on mobile to prevent text overlapping on small screens.
• Added offset, z-index & allowEscapeViewBox to chart styles to prevent hover tooltips from being hidden behind chart graphics.
• Removed dead props, fixed a few typos and replaced hardcoded values with consts.