service discovery: Add operator support

[guyarb]

What does this PR do?

Adds service-discovery check to the operator.

Motivation

Allow to control service-discovery from the operator.

Additional Notes

Minimum Agent Versions

Are there minimum versions of the Datadog Agent and/or Cluster Agent required?

• Agent: v7.58.0
• Cluster Agent: N/A

Describe your test plan

• Create kind cluster
• Follow instructions installations instructions https://github.com/DataDog/datadog-operator/blob/main/docs/how-to-contribute.md#testing-the-operator-for-development
• Use the following configuration

  apiVersion: datadoghq.com/v2alpha1
  kind: DatadogAgent
  metadata:
    name: datadog
  spec:
    global:
      env:
        - name: DD_HOSTNAME
          value: "example-kind"
      clusterName: my-example-cluster
      credentials:
        apiSecret:
          secretName: datadog-secret
          keyName: api-key
        appSecret:
          secretName: datadog-secret
          keyName: app-key
    features:
      serviceDiscovery:
        enabled: true
    override:
      nodeAgent:
        image:
          tag: 7.58.0-rc.10-linux-jmx

• Use api key to ddstaging
• Wait 5m and check you have entries in https://ddstaging.datadoghq.com/ddsql/editor?q=SELECT%20%0A%20%20%20%20a.%2A%0AFROM%20%0A%20%20%20%20discovered_service%20AS%20a%0Awhere%20a.host_name%20%3D%20%27host-kind%27%0AORDER%20BY%20%0A%20%20%20%20a.start_time&query_timeframe_end=1728826119007&query_timeframe_mode=sliding&query_timeframe_start=1728822519007

Checklist

• PR has at least one valid label: bug, enhancement, refactoring, documentation, tooling, and/or dependencies
• PR has a milestone or the qa/skip-qa label

[github-actions]

This pull request does not contain a valid label. Please add one of the following labels: bug, enhancement, refactoring, documentation, tooling, dependencies

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 71.42857% with 22 lines in your changes missing coverage. Please review.

Project coverage is 49.11%. Comparing base (7fe7979) to head (6b2b5dc).
Report is 16 commits behind head on main.

Files with missing lines	Patch %	Lines
...r/datadogagent/feature/servicediscovery/feature.go	83.33%	9 Missing and 1 partial ⚠️
internal/controller/testutils/agent.go	0.00%	10 Missing ⚠️
internal/controller/datadogslo/controller.go	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1449      +/-   ##
==========================================
+ Coverage   49.01%   49.11%   +0.09%     
==========================================
  Files         223      224       +1     
  Lines       19501    19576      +75     
==========================================
+ Hits         9559     9614      +55     
- Misses       9453     9472      +19     
- Partials      489      490       +1     

Flag	Coverage Δ
unittests	49.11% <71.42%> (+0.09%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
api/datadoghq/v2alpha1/datadogagent_default.go	89.88% <100.00%> (+0.14%)	⬆️
api/datadoghq/v2alpha1/datadogagent_types.go	100.00% <ø> (ø)
internal/controller/datadogagent/controller.go	55.17% <ø> (ø)
internal/controller/datadogslo/controller.go	56.52% <0.00%> (ø)
...r/datadogagent/feature/servicediscovery/feature.go	83.33% <83.33%> (ø)
internal/controller/testutils/agent.go	0.00% <0.00%> (ø)

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[hestonhoffman]

Approved with a tiny edit