Add annotation and label-based selector support for pruning config

[anithapriyanatarajan]

Changes

This commit introduces support for configuring pruning policies using annotation and label selectors, enabling fine-grained control over resource cleanup based on resource metadata.

Previously, pruning configuration was limited to cluster-wide or namespace scoped matching. This enhancement allows users to define pruning policies that apply to resources matching specific annotations or labels, enabling different cleanup strategies for different types of workloads within the same namespace.

Key features added:

• Annotation-based selectors for pruning configuration
• Label-based selectors for pruning configuration
• Selector-based field isolation (no fallback when selector matches)
• Enhanced configuration hierarchy: selector > namespace > global

Changes made:

• Add getFromPrunerConfigResourceLevelwithSelector function to support selector-based configuration lookup with proper fallback logic
• Add checkIfResourceMatchesAnySelector function for determining if resources match any configured selector
• Implement field isolation to prevent namespace/global fallback when resource matches a selector but specific field is undefined
• Fix annotation-based resource filtering in history limiter by using in-memory filtering instead of invalid label selectors
• Add support for fallback from specific history limits to generic historyLimit field in all matching scenarios

Submitter Checklist

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Release Notes

Tekton Pruner now supports configuring pruning policies using annotation and label selectors, enabling fine-grained control over resource cleanup based on resource metadata.
Key features added:
- Annotation-based selectors for pruning configuration
- Label-based selectors for pruning configuration
- Selector-based field isolation (no fallback when selector matches)
- Enhanced configuration hierarchy: selector > namespace > global

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[pramodbindal]

As discussed.

Should not be controlling the namespace level configuration from tekton-config as this will make tekton-config highly unreadable.

Although concept is fine but the configuration should be moved to namespace itself.

Secondly namespace level configuration limits should never exceed the global configuration so that admin has some say on the limits.

We can apply config related annotations on namespace itself just like we used to have with earlier pruner

[tekton-robot]

@anithapriyanatarajan: PR needs rebase.

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[anithapriyanatarajan]

As discussed.

Should not be controlling the namespace level configuration from tekton-config as this will make tekton-config highly unreadable.

Although concept is fine but the configuration should be moved to namespace itself.

Secondly namespace level configuration limits should never exceed the global configuration so that admin has some say on the limits.

We can apply config related annotations on namespace itself just like we used to have with earlier pruner

@pramodbindal - Limit related comments are addressed with #30. Will update further on the annotations aspect. Thankyou