fix: fix nil map panic in CompareConfigmapAndTriggerRestart when dcr.Annotations is nil

[JinVei]

What problem does this PR solve?

Problem Summary:

When CompareConfigmapAndTriggerRestart detects a configmap change and triggers
a rolling restart, it assigns directly to dcr.Annotations without checking
whether the map is initialized. If a DorisCluster CR is created without any
annotations, dcr.Annotations is nil, causing a panic that crashes the reconcile
loop.

Additionally, a copy-paste bug caused the log line to print dcr.Namespace twice
instead of dcr.Name for the CRD name field.

Observed error:

I0609 06:16:32.410860       1 doriscluster_controller.go:119] DorisClusterReconciler reconcile the update crd name adb namespace doris
I0609 06:16:32.410963       1 controller.go:221] Doris cluster is not have cn
I0609 06:16:32.411228       1 sub_controller.go:719] CompareConfigmapAndTriggerRestart TriggerRestart fe for CRD doris , namespace: doris
2026-06-09T06:16:32Z	ERROR	Observed a panic	{"controller": "doriscluster", "controllerGroup": "doris.selectdb.com", "controllerKind": "DorisCluster", "DorisCluster": {"name":"adb","namespace":"doris"}, "namespace": "doris", "name": "adb", "reconcileID": "5803f29d-1f4c-4a83-8dd7-46b31b54bb31", "panic": "assignment to entry in nil map", "panicGoValue": "\"assignment to entry in nil map\"", "stacktrace": "goroutine 234 [running]:\nk8s.io/apimachinery/pkg/util/runtime.logPanic({0x233a1d8, 0xc0032e8cf0}, {0x1d2a8a0, 0x2310bb0})\n\t/go/pkg/mod/k8s.io/apimachinery@v0.32.0/pkg/util/runtime/runtime.go:107 +0xbc\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).Reconcile.func1()\n\t/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:107 +0x112\npanic({0x1d2a8a0?, 0x2310bb0?})\n\t/usr/local/go/src/runtime/panic.go:791 +0x132\ngithub.com/apache/doris-operator/pkg/controller/sub_controller.(*SubDefaultController).CompareConfigmapAndTriggerRestart(0x0?, 0xc0027aeea0, {{0xc0014c9ff0, 0xe}, {0xc001b8e780, 0x40}, {0x0, 0x0, 0x0}, {0x0, ...}, ...}, ...)\n\t/workspace/pkg/controller/sub_controller/sub_controller.go:720 +0x285\ngithub.com/apache/doris-operator/pkg/controller/sub_controller/fe.(*Controller).Sync(0xc00028cba0, {0x233a1d8, 0xc0032e8cf0}, 0xc0027aeea0)\n\t/workspace/pkg/controller/sub_controller/fe/controller.go:93 +0x16c\ngithub.com/apache/doris-operator/pkg/controller.(*DorisClusterReconciler).Reconcile(0xc00006b580, {0x233a1d8, 0xc0032e8cf0}, {{{0xc000920c83, 0x5}, {0xc000920c80, 0x3}}})\n\t/workspace/pkg/controller/doriscluster_controller.go:149 +0x762\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).Reconcile(0xc0032e8c60?, {0x233a1d8?, 0xc0032e8cf0?}, {{{0xc000920c83?, 0x0?}, {0xc000920c80?, 0x0?}}})\n\t/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:118 +0xbf\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).reconcileHandler(0x2352ea0, {0x233a210, 0xc00068dc70}, {{{0xc000920c83, 0x5}, {0xc000920c80, 0x3}}})\n\t/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:319 +0x3a5\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).processNextWorkItem(0x2352ea0, {0x233a210, 0xc00068dc70})\n\t/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:279 +0x20e\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).Start.func2.2()\n\t/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:240 +0x85\ncreated by sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).Start.func2 in goroutine 130\n\t/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:236 +0x538\n"}
github.com/apache/doris-operator/pkg/controller/sub_controller.(*SubDefaultController).CompareConfigmapAndTriggerRestart
	/workspace/pkg/controller/sub_controller/sub_controller.go:720
github.com/apache/doris-operator/pkg/controller/sub_controller/fe.(*Controller).Sync
	/workspace/pkg/controller/sub_controller/fe/controller.go:93
github.com/apache/doris-operator/pkg/controller.(*DorisClusterReconciler).Reconcile
	/workspace/pkg/controller/doriscluster_controller.go:149
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).Reconcile
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:118
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).reconcileHandler
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:319
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).processNextWorkItem
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:279
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).Start.func2.2
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:240
2026-06-09T06:16:32Z	ERROR	Reconciler error	{"controller": "doriscluster", "controllerGroup": "doris.selectdb.com", "controllerKind": "DorisCluster", "DorisCluster": {"name":"adb","namespace":"doris"}, "namespace": "doris", "name": "adb", "reconcileID": "5803f29d-1f4c-4a83-8dd7-46b31b54bb31", "error": "panic: assignment to entry in nil map [recovered]"}
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).reconcileHandler
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:332
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).processNextWorkItem
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:279
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).Start.func2.2
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.20.0/pkg/internal/controller/controller.go:240

Fix:

• Initialize dcr.Annotations before assignment when it is nil.
• Fix log format arg: use dcr.Name instead of dcr.Namespace for the CRD name field.

Release note

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Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

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