Label-Based resource ownership - ALB and Certificates

[meneksece]

How to categorize this PR?

What this PR does / why we need it:

This PR introduces structured ownership for Application Load Balancer (ALB) and Certificate resources. By using a consistent labeling system based on the IngressClass UID, the controller can now easily find and clean up the resources it created.

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Key Changes:

• Ownership Labeling: Introduced LabelIngressClassUID (prefixed with lb.customer.label/) to track resource provenance.

• Label Merging Logic: Added logic in getAlbSpecForResources to merge user-defined labels, global config labels, and the internal ownership label (with a safety limit of 64 labels).

• Extended Interface: Updated applyCertificates to accept the IngressClass object to ensure certificates are also labeled upon creation.

Breaking changes:

[ske-prow]

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[ske-prow]

@meneksece: The following test 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-cloud-provider-stackit-verify	a14b123	link	true	/test pull-cloud-provider-stackit-verify

Full PR test history. Your PR dashboard. Command help for this repository.
Please help us cut down on flakes by linking this test failure to an open flake report or filing a new flake report if you can't find an existing one. Also see the gardener testing guideline for how to avoid and hunt flakes.

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