Dashboard Inheritance

**Why is this needed**: I work in a team managing observability for thousands of instrumented applications. I've made a general dashboard that shows a lot of useful information and has a variable+dropdown for the app name. In theory, this should be very simple to navigate, but we've got a ton of users who are brand new to observability, and we've found that it's sometimes a challenge to get them to 1. Locate this dashboard 1. Locate the dropdown 1. Select the app name Ideally, I would like to give brand new users who know nothing about Grafana the ability to 1. Naively search for the app name in the global search bar 1. Click the `<app_name> Monitoring` result If I want to do this right now, my only option seems to be to write some code to copy the contents of this general dashboard and make a brand new dashboard specifically for this app name, but that would quickly result in an explosion of disk space usage just for these service-specific dashboards. **What would you like to be added**: We could achieve the above goal while keeping disk space usage minimal if there were something like dashboard inheritance/virtualization/symlink/insert_sexy_tech_term_here. By this I mean: * one parent dashboard (e.g., `App Monitoring Template`) * has everything that a normal dashboard has, e.g., * rows * visualizations * data links, * dropdowns for non-hidden variables (e.g., SLO values like 95th percentile latency) * etc. * hundreds to thousands of child dashboards whose json essentially looks like ``` { "type": "inherited", "name": "Foo Monitoring", # name of new child dashboard "base": "App Monitoring Template", # name of template dashboard "values": { # values used to fill in the hidden variables in the template dashboard "app_name": "Foo" } } ``` NB: I've taken a look at [this issue](https://github.com/grafana/grafana/issues/5657) and [this one](https://github.com/grafana/grafana/issu…