Implement a config file for the Value stream dashboard

What does this MR do and why?

Implement an optional YAML config file for the Value stream dashboard.

In addition to using query parameters to view project metrics, you can also use a YAML config file to customize the dashboard.

Screenshots or screen recordings

YAML load error

Namespace load error

Multiple namespaces

Custom title/descriptions

How to set up and validate locally

Setup configuration Project

1. On the top bar, select Main menu.
2. Select Groups and find your group.
3. On the left sidebar, select Settings > General.
4. Navigate to Analytics Dashboards, click Expand.
5. Select the Project that you would like to use to store your YAML configuration file
6. Click Save changes

Setup configuration file

1. On the top bar, select Main menu.
2. Select Projects and find your project.
3. Create a .gitlab/analytics/dashboards/value_streams/value_streams.yaml file in the default branch

Configuration options

# title - Change the title of the Value Streams Dashboard. [optional]
title: 'Custom Dashboard title'

# description - Change the description of the Value Streams Dashboard. [optional]
description: 'Custom description'

# widgets - List of widgets that contain panel settings.
#   title - Change the title of the panel. [optional]
#   data.namespace - The Group or Project path to use for the chart panel.
widgets:
  - title: 'My Custom Project'
    data:
      namespace: group/my-custom-project
  - data:
      namespace: group/another-project
  - title: 'My Custom Group'
    data:
      namespace: group/my-custom-group
  - data:
      namespace: group/another-group

Flightjs Example

widgets:
  - data:
      namespace: flightjs
  - data:
      namespace: flightjs/flight

Seed analytics data

1. Seed cycle analytics data (and optionally DORA metrics data)
2. Visit the value streams dashboard: http://gdk.test:3000/groups/${YOUR_GROUP}/-/analytics/dashboards

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #385716 (closed)