Generate reference documentation locally

Most reference documentation for fuchsia.dev is generated through an infra recipe that calls the docsgen tool.

The docsgen tool calls various other tools that generate reference documentation, such as:

Once the infra recipe generates this documentation, it is pushed to the reference-docs repository.

Then, the documentation is published to the reference section of fuchsia.dev, which is fuchsia.dev/reference/.

There is also manually created reference documentation that is usually published to a URL that is prefixed with fuchsia.dev/fuchsia-src/reference/. The source for this documentation is in //docs/reference/.

Generate reference documentation locally

In some cases, it can be useful to run docsgen locally to review the output of the various tools that generate documentation.

To run docsgen locally:

Add docsgen to fx set. For example, you can use the minimal configuration:
```
fx set minimal.x64 --with //tools/docsgen
```
Build and run docsgen:

Note: Running docsgen also implicitly runs doc-checker. For more information about doc-checker, see Automated documentation checks
```
fx build tools/docsgen
```
Note: Some of the reference documentation is packaged in a .zip file, so make sure to extract the documentation.

You can then review the built reference documentation in //out/default/obj/docsgen of your Fuchsia checkout.