fix: add deprecation notice to SourceType field in ApplicationStatus

SourceType (singular string) and SourceTypes (plural array) both exist
in ApplicationStatus with no guidance on which to use. Add deprecation
comment to SourceType pointing to SourceTypes, consistent with how
ObservedAt deprecation is documented in the same struct.

Fixes #27766

Author: Shreya2005-2005

pkg/apis/application/v1alpha1/types.go

@@ -1213,6 +1213,8 @@ type ApplicationStatus struct {
 	// Deprecated: controller no longer updates ObservedAt field
 	ObservedAt *metav1.Time `json:"observedAt,omitempty" protobuf:"bytes,8,opt,name=observedAt"`
 	// SourceType specifies the type of this application
+	//
+	// Deprecated: Use SourceTypes instead, which supports both single and multi-source applications
 	SourceType ApplicationSourceType `json:"sourceType,omitempty" protobuf:"bytes,9,opt,name=sourceType"`
 	// Summary contains a list of URLs and container images used by this application
 	Summary ApplicationSummary `json:"summary,omitempty" protobuf:"bytes,10,opt,name=summary"`