FE: limit variable values by the selected time range

[gitstart]

Fixes #2022

Created two new properties for the custom variables.

The user can create additional value groups and time range selections. Each time range selection can be applied to one or more groups. The values ​​of these groups will be displayed in the dropdown if the time defined in the dashboard is compatible with what was previously selected, and this is valid for each time range selection.

https://www.loom.com/share/efb2ab56b897465aa8c57b764f9a427d

[srikanthccv]

Can you help me understand how does this fix the issue?

[gitstart]

Can you help me understand how does this fix the issue?

Hi, @srikanthccv
The problem is that currently there is no control over the number of custom variables displayed on the screen, what this PR does is make it possible to configure which variables should appear in which period of time, if the time matches the time selected in the selector at the top of the screen, the corresponding variables will appear.

This is done as follows:
The user creates separate groups of variables, which can contain one or more variables, and applies a time restriction on the groups, the variables belonging to that group will be shown if they are within the time range