Added legend options for charts

[PratikshaPatil77]

Description

Added customizable legend options such as Legend Modes (List, Table, Hidden), Legend Placements (Bottom, Right, left) and Legend Value Displays (Name, Value, Percentage) for dashboard panels, offering users the ability to choose.

Fixes #135

Checklist:

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• [ x ] I have removed all print-debugging and commented-out code that should not be merged.
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[sonamgupta21]

1. The Legends Placement dropdown initially remains open and doesn't close when an option is selected.
2. When clicking any option, changes should directly reflect on the chart. Currently, we have to rerun the query after selecting an option.
3. Currently, the changes do not reflect if we save the dashboard and revisit it. We should store the legend-related values in the dashboard JSON.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 30.82%. Comparing base (7f68694) to head (02745a8).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #461      +/-   ##
===========================================
+ Coverage    30.81%   30.82%   +0.01%     
===========================================
  Files          127      127              
  Lines        35435    35435              
===========================================
+ Hits         10918    10924       +6     
+ Misses       23213    23208       -5     
+ Partials      1304     1303       -1     

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[AndrewHess]

There's a bunch of .fashttp.gz files that you should remove from this PR. I think also the defaultDB and querynodes file changes/additions are not needed, right? If they're not needed, you should remove those from the PR