⚠️ improve capi provider

[guilhem]

Description

• Refactors the CAPI provider to be constructed without a manager and configured via an explicit SetupWithManager.
• Adds kubeconfig hashing to detect changes and re-engage clusters when configs rotate.
• Improves cluster lifecycle management (cache sync, removal, indexers) and simplifies the startup flow.

Key changes

• Updates the example to build the provider first, then create the multi-cluster manager, and start a single manager instance.
• The provider now:
  • reads raw kubeconfig bytes and parses locally,
  • detects kubeconfig changes via SHA-256,
  • re-engages clusters when kubeconfig changes,
  • tracks engaged clusters with RW locks and exposes list functionality.
• Field indexers apply to existing and future clusters without holding locks during indexing.

[k8s-ci-robot]

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[k8s-ci-robot]

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[embik]

Hey @guilhem, this is a great set of changes, thank you for bringing the CAPI provider more in line with the remaining providers in this repository. I have two comments.

In addition, I have a question: Your description has references (?) like F30844c7L94R94. What is that?

[guilhem]

Hey @guilhem, this is a great set of changes, thank you for bringing the CAPI provider more in line with the remaining providers in this repository. I have two comments.

Thanks :)

I jsut how to fix tests.

In addition, I have a question: Your description has references (?) like F30844c7L94R94. What is that?

Copilot "tried" to generate a description
I changed to another