fix: correct Kubernetes deployment manifests

[dodjdnh]

Summary

Fixes #1570.

This PR addresses three Kubernetes deployment-manifest correctness issues:

• Define Namespace/dubbo-system before the resources that use it.
• Remove the two invalid nodePort fields from the Nacos ClusterIP Service.
• Correct the Grafana service DNS in the Dubbo Admin ConfigMap.

The change is contained in one commit, cafc748bd51c730c7e1b9f2cdc135f8aed14667c (fix: correct Kubernetes deployment manifests), and three files under release/kubernetes/dubbo-system/.

Changes

1. Add release/kubernetes/dubbo-system/00-namespace.yaml to define dubbo-system. The filename places the Namespace before dubbo-admin.yaml and nacos.yaml when applying the directory with kubectl apply -f release/kubernetes/dubbo-system.
2. Keep the Nacos Service as ClusterIP, preserving its port and targetPort values while removing nodePort: 30848 and nodePort: 31848. Its internal service address is unchanged.
3. Change the Admin ConfigMap Grafana URL from http://grafana.monitoringg.svc:3000 to http://grafana.monitoring.svc:3000, matching the included Grafana Service.

Validation

• git diff --check: PASS.
• The same external D002 deployment oracle checks A1 (Namespace definition), A2 (Namespace file precedes every manifest containing a dubbo-system namespaced resource), B1 (valid Nacos ClusterIP fields), B2 (Kubernetes server-side dry-run), and C (Grafana DNS). Before the filename correction it reported A1 PASS, A2 FAIL, B1/B2/C PASS; after the correction, all five checks PASS. A2 evaluates the actual file order rather than requiring a particular filename.
• kubectl apply --dry-run=client -f release/kubernetes/dubbo-system -o name lists the Namespace before the Dubbo Admin and Nacos resources.
• The Nacos manifest passes a Kubernetes API server-side dry-run; this is validation, not a real apply.

A disposable Kubernetes cluster was not available, so a real fresh-cluster Deployment Smoke Test has not been performed. This PR does not claim that full deployment verification passed.

Scope

This PR does not change dashboard provisioning, Jaeger datasource setup, OTel Collector, Instance/Service Trace queries, log observability, or cross-signal navigation.

Areas affected

• Docs
• Installation
• User Experience
• Dubboctl
• Console
• Core Component

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[dodjdnh]

我已经在本地基于当前这个 PR，实现了后续的 D003 Kubernetes Observability provisioning（Kubernetes 可观测性配置） 改动。

D003 中 Admin 使用的 Dashboard URL 依赖于 D002 引入的、修正后的 Grafana Service DNS。因此，将 D003 暂时叠加在当前 PR 之上，可以保留这个前置依赖，同时避免重复实现 D002 中已经完成的修复。

目前，静态 provisioning 检查已经通过；运行时验证仍然尚未完成。

等 D002 合并之后，我会把 D003 rebase 到更新后的 develop 分支之上，然后将它作为一个独立的 PR 提交。