✨ Introduce generics to providers

[Danil-Grigorev]

What this PR does / why we need it:

This implementation achieves the following:

• Separate each provider in it’s own reconciler.
• Share common logic between reconcilers via phase functions, while preserving the original provider type per reconciler. Reconcilers can reuse common methods without restrictions or add their own, applicable only for the reconciler itself.
• Unifies Clusterctl provider generation for plugin and provider reconcilers under providers package import. Removes the need to do switch cases on provider types in multiple locations. Only one needs to be up-to-date now.
• Reconcile is split into stages. These are defined like this:

	PreflightChecks(ctx context.Context, provider P) []ReconcileFn[P, Group[P]]
	ReconcileNormal(ctx context.Context, provider P) []ReconcileFn[P, Group[P]]
	ReportStatus(ctx context.Context, provider P) []ReconcileFn[P, Group[P]]
	ReconcileDelete(ctx context.Context, provider P) []ReconcileFn[P, Group[P]]

Each provider can extend/replace/re-order the phases for each stage at their liking.

Additionally a couple of issues are fixed:

• Core provider singleton check. Previously Core provider was using name check for differentiating other core providers, but the core provider can only be named cluster-api.
• Pre-flight checks are now unique per each provider, type casting to check provider type to perform some validation is no longer needed.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

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[Danil-Grigorev]

/test pull-cluster-api-operator-test-main

[k8s-ci-robot]

PR needs rebase.

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/lifecycle stale

[furkatgofurov7]

@Danil-Grigorev can you please rebase this PR if this change is needed and to get things going?

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/lifecycle rotten

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/close

[k8s-ci-robot]

@k8s-triage-robot: Closed this PR.

In response to this:

The Kubernetes project currently lacks enough active contributors to adequately respond to all issues and PRs.

This bot triages PRs according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
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/close

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[k8s-ci-robot]

@Danil-Grigorev: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-cluster-api-operator-e2e-main	d365a10	link	true	/test pull-cluster-api-operator-e2e-main
pull-cluster-api-operator-apidiff-main	d365a10	link	false	/test pull-cluster-api-operator-apidiff-main
pull-cluster-api-operator-verify-main	d365a10	link	true	/test pull-cluster-api-operator-verify-main
pull-cluster-api-operator-build-main	d365a10	link	true	/test pull-cluster-api-operator-build-main
pull-cluster-api-operator-test-main	d365a10	link	true	/test pull-cluster-api-operator-test-main
pull-cluster-api-operator-make-main	d365a10	link	true	/test pull-cluster-api-operator-make-main

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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[Danil-Grigorev]

/remove-lifecycle rotten