Set heatmap color range configurable

[sapk]

Should fix #5164 by allowing the customization of the color range along theming

Suggestion to use with arc-green theme : ['#2d303b', '#80bb46']

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Codecov Report

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The diff coverage is 100%.

@@            Coverage Diff            @@
##             master    #5165   +/-   ##
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  Coverage          ?   37.49%           
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  Files             ?      309           
  Lines             ?    45786           
  Branches          ?        0           
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  Hits              ?    17166           
  Misses            ?    26158           
  Partials          ?     2462

Impacted Files	Coverage Δ
modules/setting/setting.go	48.24% <ø> (ø)
modules/templates/helper.go	49.4% <100%> (ø)

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[filipnavara]

Wouldn't it make more sense to have HEATMAP_COLOR_RANGE in the theme?

[sapk]

@filipnavara theme only load a custom CSS if not the default. I choose the most simple fix that also allow customisation if used with an others theme or custom template but maybe we could improve it by setting the default based on theme used.

[lunny]

I like @filipnavara 's idea.

[lafriks]

But our themes has only css I think so that not really possible currently but I would also better see this added to themes somehow than in configuration

[gsantner]

Have also noticed a problem with scale, take a look at https://goblinrefuge.com/mediagoblin/u/gsantner/m/gitea-heatmap-issue/ . Thought fits here because people worked on heatmap are already in this issue :D.

[lunny]

@gsantner Please fire another issue to describe that. Or maybe your issue has been fired on #5191 ?

[gsantner]

Oh, right it's nr 3. there