[Fleet] Display k8 deployment instructions in fleet mode

[mukeshelastic]

Describe the feature:
For regular agents which are deployed as agent binaries on hosts, the installation and enrollment instructions are described in "Add agent ->enroll in fleet" tab seen below:

These instructions need to be tailored for kubernetes where the agent is deployed as daemonset pod on each node and not as binary on VM host.

When users follow these instructions, these agents are managed by fleet and their status can be seen in agents tab below. If the daemonset is removed because a worker node is recycled then the agent is shown in the offline state.

Similar to the regular agent, for these managed k8s agent:

• clicking on agent details or log, should show you logs from agent, filebeat, metricbeat containers run by the agent
• can uneroll agent
• copy to another agent policy

[elasticmachine]

Pinging @elastic/fleet (Team:Fleet)

[MichaelKatsoulis]

After a discussion with @akshay-saraswat and @tetianakravchenko there are some issues we have to tackle regarding the Enroll in Fleet page.

1. Step 1 (Download the Elastic Agent to your host) contains instructions about downloading the agent binary to your machine which is later needed to start the agent. In case of Kubernetes the binary is not needed so this step can be misleading.
2. In Step 3 after a policy which contains Kubernetes integrations is selected, the Kubernetes platform can be set as default but the command (kubectl apply -f elastic-agent-managed.yml) has 2 prerequisites.
   • The user needs to have downloaded the proposed manifest
   • Env vars (FLEET_URL and FLEET_ENROLLMENT_TOKEN) need to have the correct values

One way to overcome those issues could be:

1. Change the order of the steps. Step 1 will be the policy selection.
2. In case policy does not contain Kubernetes integration then step 2 will the previous step 1(Download the Elastic Agent to your host) and step 3 same as before.
3. In case policy contains Kubernetes integration, step 2 will change to Download Kubernetes Manifest. Like in standalone mode (step 3) the updated manifest (with the correct image and env vars) will be shown together with a button to download it.
4. Step 3 will contain just Kubernetes as available platform with the command to kubectl apply -f elastic-agent-managed-kubernetes.yaml (which will be the name of the downloaded file).

@mukeshelastic, @nchaulet , @jen-huang any thoughts on this proposal ?

[jen-huang]

@mostlyjason What do you think about the above proposal? Especially around moving select policy to step 1 and download agent binary to step 2 across the board. I think this is actually reasonable for the user to select what they want to ingest (aka selecting policy and seeing all its integrations) as part of step 1.

[mostlyjason]

That makes sense. I think this is also consistent with our future plan to move the download instructions lower as part of this redesign #80841.

[amitkanfer]

@amar-rama-elastic @ari-aviran @einatjacoby

[amar-rama-elastic]

@snehsach19

team -> The CSP and AWP team are deeply invested in this workflow and eager to see it be excellent :-) Simplifying the policies that are made available, what integrations comes with those policies and how to best communicate it to the user as part of the installation process. Would it be possible to get on a zoom with y'all and explore the end to end figma flow being proposed?

/cc @mukeshelastic @dimadavid