Replace fmt.Printf/Println with logr.logger

[yeahdongcn]

Closes #

📑 Description

Replace fmt.Printf/Println with logr.logger for more structured and leveled logging.

2024-07-31T18:33:05+08:00       INFO    controller-runtime.metrics      Metrics server is starting to listen    {"addr": ":8080"}
2024-07-31T18:33:05+08:00       INFO    setup   starting manager
2024-07-31T18:33:05+08:00       INFO    starting server {"path": "/metrics", "kind": "metrics", "addr": "[::]:8080"}
2024-07-31T18:33:05+08:00       INFO    Starting server {"kind": "health probe", "addr": "[::]:8081"}
2024-07-31T18:33:05+08:00       INFO    Starting EventSource    {"controller": "k8sgpt", "controllerGroup": "core.k8sgpt.ai", "controllerKind": "K8sGPT", "source": "kind source: *v1alpha1.K8sGPT"}
2024-07-31T18:33:05+08:00       INFO    Starting Controller     {"controller": "k8sgpt", "controllerGroup": "core.k8sgpt.ai", "controllerKind": "K8sGPT"}
2024-07-31T18:33:05+08:00       INFO    Starting workers        {"controller": "k8sgpt", "controllerGroup": "core.k8sgpt.ai", "controllerKind": "K8sGPT", "worker count": 1}
2024-07-31T18:33:05+08:00       INFO    Reconciling K8sGPT      {"controller": "k8sgpt", "controllerGroup": "core.k8sgpt.ai", "controllerKind": "K8sGPT", "K8sGPT": {"name":"k8sgpt-sample-localai","namespace":"k8sgpt-operator-system"}, "namespace": "k8sgpt-operator-system", "name": "k8sgpt-sample-localai", "reconcileID": "863bf79d-ce72-4e4e-8e01-a339bc5fb51e"}
2024-07-31T18:33:05+08:00       INFO    Finished Reconciling k8sGPT     {"controller": "k8sgpt", "controllerGroup": "core.k8sgpt.ai", "controllerKind": "K8sGPT", "K8sGPT": {"name":"k8sgpt-sample-localai","namespace":"k8sgpt-operator-system"}, "namespace": "k8sgpt-operator-system", "name": "k8sgpt-sample-localai", "reconcileID": "863bf79d-ce72-4e4e-8e01-a339bc5fb51e"}

✅ Checks

• My pull request adheres to the code style of this project
• My code requires changes to the documentation
• I have updated the documentation as required
• All the tests have passed

ℹ Additional Information

Testing done:

1. make build -> ok
2. make test -> ok
3. docker-buildx -> ok