Add the bootstrap command to the agent creation popup

Release notes

Problem to solve

As an Application Operator, I want to manage my agentk installation with FluxCD.

Proposal

With Easy bootstrapping of k8s functionality with th... (&12594 - closed) released, we can add support for the glab cluster agent bootstrap command to the agent registration popup.

Microcopy at the top:

Bootstrap the agent with Flux

If Flux is installed in the cluster, you can install and register the agent from the command line:

glab cluster agent bootstrap <agent-name>

You can view a list of options with --help.

If you're [bootstrapping the agent with Flux](link_to_docs), you can close this dialog.

Docs link:

https://docs.gitlab.com/ee/user/clusters/agent/install/#bootstrap-the-agent-with-flux-support-recommended

Intended users

• Allison (Application Ops)

Feature Usage Metrics

No metrics to implement here

Does this feature require an audit event?

No

Implementation plan

1. Update install_agent_modal to include the new section.
2. The strings are located in the I18N_AGENT_MODAL constant.
3. To add a code block with the glab command, use a similar approach as in the connect_to_agent_modal.
4. Update the corresponding specs