feat(chart): add automountServiceAccountToken support, more commonAnnotations

[Jacobious52]

What type of PR is this?

/kind feature

What this PR does / why we need it:

This PR adds two new features to the Helm chart:

1. serviceAccount.automountServiceAccountToken

Allows controlling whether the service account token is automatically mounted. This is useful for security hardening when using projected volumes for manual token access instead of automatic mounting.

Usage:

serviceAccount:
  automountServiceAccountToken: false

Only renders when explicitly set, preserving default Kubernetes behavior (no diff when omitted).

2. commonAnnotations

Adds the ability to specify annotations that will be applied to all resources created by the chart. This is useful for:

• Organizational metadata
• Ownership tracking
• Policy enforcement (e.g., cost allocation, compliance)

Usage:

commonAnnotations:
  my-org.com/owner: platform-team
  my-org.com/cost-center: "12345"

Applied to: ServiceAccount, ClusterRoles, ClusterRoleBindings, RoleBinding, Service, Deployment, PDB, APIService.

3. Arg ordering improvement

Moves --secure-port arg after defaultArgs for better flexibility when users need to control argument ordering.
Required when using a custom image and entry point and need to specify metrics-server binary.

Which issue(s) this PR fixes:

None - new feature request.

Special notes for your reviewer:

• All changes are backward compatible
• No Chart.yaml modifications per contributing guidelines
• When automountServiceAccountToken is not set, no diff is produced (uses Kubernetes default)
• commonAnnotations is merged with resource-specific annotations (e.g., service.annotations), with resource-specific taking precedence

Does this PR introduce a user-facing change?

chart: Add serviceAccount.automountServiceAccountToken and commonAnnotations support

---

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[stevehipwell]

Thanks for the PR @Jacobious52, I've added a few review comments.

FYI you're overlapping with #1752.

[stevehipwell]

Suggested change

	# automountServiceAccountToken: true
	automountToken:

This is already in the service account context, and all values need to be declared in the values file.

You can use the following pattern to set the field.

{{- if ne .Values.serviceAccount.automountToken nil }}
...
{{- end }}

[stevehipwell]

If you're making this change for security hardening you'll likely also need to modify the deployment.

[stevehipwell]

I don't agree with this change. FYI this chart is designed to work with the official image or a hardened image built from the upstream source.

[Jacobious52]

No worries. The issue for our usage is for our hardened environment we are required to use a custom entry point in a hardened image forked from upstream and call the application binary as the first arg.
e.g.

args:
- /metrics-server
- args.

[Jacobious52]

Thanks for your review @stevehipwell. I see I've overlapped with #1752 for annotations and our hardened image requirements are unique to us. So I'll close this and we'll just maintain and internal fork.

[stevehipwell]

@Jacobious52 some of your annotation changes are net new so happy to take them. Was just a heads up and a chance to compare patterns. Also happy to take the service account changes.

[Jacobious52]

@stevehipwell Ah I jumped the gun there. Okay happy to try reconcile the annotation changes, and fix up SA token and add to the deployment.

I'll leave the arg ordering out.

Give me a bit of time and I'll make a commit. Cheers