chore(deps): upgrade k8s.io/client-go to v0.36.2

[bernot-dev]

• Upgrade k8s.io/client-go, k8s.io/api, and k8s.io/apimachinery to v0.36.2.
• Remove obsolete k8s.io/klog/v2 replace directive in go.mod to support klog.NewContext and textlogger required by updated apimachinery.
• Add klogGokitSink logr.LogSink adapter in cmd/prometheus to bridge klog/v2 with go-kit/log.
• Update watch error handlers in discovery/kubernetes to use cache.WatchErrorHandlerWithContext.
• Wrap cache.ListWatch with cache.ToListWatcherWithWatchListSemantics in discovery/kubernetes informers so Reflector correctly detects client capabilities when streaming initial events (WatchListClient feature gate).

[gemini-code-assist]

Code Review

This pull request upgrades Go to version 1.26.0, updates various Kubernetes dependencies, and removes the replace directive for klog/v2. It introduces a custom klogGokitSink to bridge klog/v2 with Go-kit logging, and updates Kubernetes discovery informers to utilize watch list semantics and context-aware error handlers. Feedback on these changes highlights that the current WithName implementation in klogGokitSink is a no-op and should be updated to preserve sub-logger names while optimizing slice allocations. Additionally, defensive nil checks for d.client should be added in kubernetes.go to prevent potential nil pointer dereferences.

[gemini-code-assist]

The current implementation of WithName is a no-op that simply returns s. This completely discards the sub-logger names configured by client-go (e.g., reflector, informer), making it very difficult to identify which component produced a log message.

To preserve this crucial context, we should store the logger name in the klogGokitSink struct, append new names in WithName, copy the name in WithValues, and include it as a "logger" key in the log output when it is not empty. Additionally, we can optimize the slice allocations in Info and Error by pre-allocating the slice with the correct capacity.

type klogGokitSink struct {
	logger   log.Logger
	maxLevel int
	name     string
}

func (s *klogGokitSink) Init(info logr.RuntimeInfo) {}
func (s *klogGokitSink) Enabled(level int) bool { return level <= s.maxLevel }
func (s *klogGokitSink) Info(level int, msg string, keysAndValues ...any) {
	if level > s.maxLevel {
		return
	}
	kvs := make([]any, 0, 4+len(keysAndValues)+2)
	kvs = append(kvs, "level", "info", "msg", msg)
	if s.name != "" {
		kvs = append(kvs, "logger", s.name)
	}
	kvs = append(kvs, keysAndValues...)
	_ = s.logger.Log(kvs...)
}
func (s *klogGokitSink) Error(err error, msg string, keysAndValues ...any) {
	kvs := make([]any, 0, 6+len(keysAndValues)+2)
	kvs = append(kvs, "level", "error", "msg", msg, "err", err)
	if s.name != "" {
		kvs = append(kvs, "logger", s.name)
	}
	kvs = append(kvs, keysAndValues...)
	_ = s.logger.Log(kvs...)
}
func (s *klogGokitSink) WithValues(keysAndValues ...any) logr.LogSink {
	return &klogGokitSink{
		logger:   log.With(s.logger, keysAndValues...),
		maxLevel: s.maxLevel,
		name:     s.name,
	}
}
func (s *klogGokitSink) WithName(name string) logr.LogSink {
	newName := name
	if s.name != "" {
		newName = s.name + "." + name
	}
	return &klogGokitSink{
		logger:   s.logger,
		maxLevel: s.maxLevel,
		name:     newName,
	}
}

[gemini-code-assist]

To prevent potential nil pointer dereferences or panics in unit tests or custom environments where d.client might not be fully initialized, we should defensively check that d.client is not nil before wrapping the ListWatch with cache.ToListWatcherWithWatchListSemantics.

Suggested change

	if listWatch, ok := lw.(*cache.ListWatch); ok {
	lw = cache.ToListWatcherWithWatchListSemantics(listWatch, d.client)
	}
	if listWatch, ok := lw.(*cache.ListWatch); ok && d.client != nil {
	lw = cache.ToListWatcherWithWatchListSemantics(listWatch, d.client)
	}

[gemini-code-assist]

To prevent potential nil pointer dereferences or panics in unit tests or custom environments where d.client might not be fully initialized, we should defensively check that d.client is not nil before wrapping the ListWatch with cache.ToListWatcherWithWatchListSemantics.

Suggested change

	if listWatch, ok := lw.(*cache.ListWatch); ok {
	lw = cache.ToListWatcherWithWatchListSemantics(listWatch, d.client)
	}
	if listWatch, ok := lw.(*cache.ListWatch); ok && d.client != nil {
	lw = cache.ToListWatcherWithWatchListSemantics(listWatch, d.client)
	}