Docs: Plugins doc reorganization, part 1 (#69864)

* Initial commit

* Prettier fixes

* Doc-validator fixes part 1

* Doc-validator fixes part 2

* More doc-validator fixes

* More doc-validator fixes

* Test

* link test

* Linnk test

* Link test

* More fixes

* More fixes

* Doc-validator fixes

* Doc-validator fixes

* fix broken link

* Fix

* Testing

* Doc fixes

* Link fixes

* Fix links

* Update docs/sources/developers/plugins/create-a-grafana-plugin/_index.md

Co-authored-by: David Harris <david.harris@grafana.com>

* Testing

* Testing

* Testing

* Testing

* Doc-validator fixes

* Doc-validator fixes

* Doc-validator fixes

* Fix broken links for plugins reorganization project

* Prettier fixes

* Prettier fixes

* Incorporate reviewer feedback

* Link fixes

* Link fixes

* Link fixes

* Link fix

* Deleted space

* Codeowners fix

* Change grafana.com links to absolute URLs for Hugo

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Co-authored-by: David Harris <david.harris@grafana.com>

docs/sources/shared/tutorials/plugin-anatomy.md

@@ -14,7 +14,7 @@ While certain plugin types can have specific configuration options, let's look a
 
 - `type` tells Grafana what type of plugin to expect. Grafana supports three types of plugins: `panel`, `datasource`, and `app`.
 - `name` is what users will see in the list of plugins. If you're creating a data source, this is typically the name of the database it connects to, such as Prometheus, PostgreSQL, or Stackdriver.
-- `id` uniquely identifies your plugin, and should start with your Grafana username, to avoid clashing with other plugins. [Sign up for a Grafana account](/signup/) to claim your username.
+- `id` uniquely identifies your plugin, and should start with your Grafana username, to avoid clashing with other plugins. [Sign up for a Grafana account](https://grafana.com/signup/) to claim your username.
 
 To see all the available configuration settings for the `plugin.json`, refer to the [plugin.json Schema](/docs/grafana/latest/plugins/developing/plugin.json/).