Fix #220 & #213 + Untracked bugs

[theperu]

🎯 Purpose

Fixing the following issues:

• iOS: Dashboard graph is not precise #220: Fixed the issue with the weird display of the line graph by lowering the curve smoothness. This makes the graph a bit more pointy but it should be more accurate
• iOS: Dashboard: budget section is not working #213: Before a budget was displayed only if at least a transaction was added for the current month, now they are always displayed
• On the graphs page the line graph wasn't displaying the months but the current month days. Now it is fixed by specifying Period.year (Untracked)
• When no budget is added we had an empty section, now I added a simple text

📱 Changes Made

SEE SECTION ABOVE

🧪 Testing Instructions

Fix #220

1. Add a big income transaction
2. Add a small expense for the day after
3. You shouldn't see a big curve as before

Fix #213

1. Add a budget for a category that has no transaction this month
2. Check that in the dashboard the budget is displayed anyways

Untracked graphs page bug

1. Add some data for current and previous month
2. Check that on the graphs page the line chart lists the months in the X axis

Untracked no budget bug

1. Start the app with no budgets
2. Check that the budget section in the Dashboard displays a text instead of an empty space

📸 Screenshots/Videos

N/A

🔍 Review Checklist

• Code follows project style guidelines
• Documentation updated
• Widgets are properly disposed