[Enhancement] Add period range to enable custom time range in analytics

[JaanikaTalvistu]

AS AN analyst
I WANT to apply a custom time range period
SO THAT I can look at more specific time ranges that is not day, week or month specific

All changes are described under the analytics Overview page.

Acceptance Criteria

• Add an additional button next to Month, on the right side.
• The button is called Period / Periood
• The first date has to be either today or older (cannot be in the future).
• Date picker opens up a calendar (as-is).
• When picking a first date then the second date will not change automatically. It will stay as it previously was selected.
• Second date cannot be older than the first date (when first date is 27.07 then second date cannot be 26.07 or older)
• When second time range is selected then all metrics will automatically adjust to the selected time period.
• When the period is more than 1 month then the graph will show the total chat values in weekly steps.
• Hovering will show the weekly range from Monday to Sunday (example: 20.07.2026 - 26.07.2026)
• When the period is more than 5 months then a warning icon will be shown next to the bar chart title.
• Warning icon is similar to the flag in Figma. Instead of the text on the right, the text will be displayed as a tooltip.
• The warning icon tooltip text is the following:
  • EE version: Valitud on pikk ajaperiood, mis mõjutab graafiku visuaalset välimust. Parima vaate saamiseks vähenda ajaperioodi pikkust.
  • ENG version: A long time period is selected, which affects the visual appearance of the chart. Reduce the length of the time period for a better overview.
• Date range will be added to preferences (when navigating on different subcategories then the date range will be remembered).

Today button changes

• When Day is selected the button "Today" needs to be renamed to "This day" / "Tänane päev".
• When Week is selected the button "Today" needs to be renamed to "This week" / "See nädal".
• When Month is selected the button "Today" needs to be renamed to "This month" / "See kuu".
• When on the Period range then "Today" button is "This day" / "Tänane päev".
• When on Period and "This day" is pressed then the range will change from Period to Day and the date range will be today's date.

[ketlyiouriev]

TEST ENV:

"Date range will be added to preferences (when navigating on different subcategories then the date range will be remembered)." → the "Day"/"Week"/"Month"/"Period" selection is remember correctly BUT the actual from-to dates are not, they always reset to current day/week/month. EXAMPLE: 1) after selecting "Day", today's date is set automatically; 2) now choose yesterday's date; 3) after refresh, the "Day" is correctly kept selected BUT from-to dates are back to today's date.

[ketlyiouriev]

TEST ENV - OK!