[v10.4.x] Docs: add legends shared content (#88195)

* Docs: add legends shared content (#86814)

* Updated shared file name and added missing options

* Added legend options 1 shared file to relevant visualizations

* Updated shared file name and corrected options

* Added legend options 2 shared file to relevant visualizations

* Updated legend content for heatmap and pie chart

* Added where shared legend files are used in each file

* Moved intro text out of viz pages into legend options shared files

* Added reasoning to front matter of shared files

* Added reasoning to front matter of shared files

* Fixed version interpolation and added cloud links

* Updated links in shared files

(cherry picked from commit dad3069594)

* Ran prettier

docs/sources/panels-visualizations/visualizations/histogram/index.md

@@ -134,11 +134,9 @@ Transparency of the gradient is calculated based on the values on the Y-axis. Th
 
 Gradient color is generated based on the hue of the line color.
 
-{{< docs/shared lookup="visualizations/legend-mode.md" source="grafana" version="<GRAFANA_VERSION>" >}}
+## Legend options
 
-### Legend calculations
-
-Choose a [standard calculations](ref:standard-calculations) to show in the legend. You can select more than one.
+{{< docs/shared lookup="visualizations/legend-options-1.md" source="grafana" version="<GRAFANA_VERSION>" >}}
 
 ## Value mappings