Schema: convert dashboards from v1beta1 to v2beta1 (#109037)

- Implement full conversion pipeline from v1beta1 → v2beta1
- Ensure frontend–backend parity for all dashboard serialization paths
- Add automatic data loss detection for conversions (panels, queries, annotations, links, variables)
- Extract atomic conversion functions for v0 → v1beta1 → v2alpha1 → v2beta1
- Introduce conversion metrics and detailed logging for loss tracking
- Normalize datasource resolution, defaults, and annotation processing
- Improve panel layout serialization and y-coordinate normalization
- Fix inconsistencies in nested panels and collapsed row behavior
- Refine variable handling:
  - Filter refId from variable query specs
  - Default variable refresh to 'never' (matches frontend)
  - Fix constant and interval variable handling for missing queries
- Unify schema defaults (enable, hide, iconColor, editable, liveNow)
- Fix pluginId usage (UID vs type) and datasource references
- Fix metrics.go bug swallowing errors (return nil → return err)
- Add tests for version-specific conversion error handling
- Add data loss detection tests using source/target version comparison
- Clean up lint issues, legacy code, and redundant files
- Update OpenAPI snapshots and migrated dashboards
- Improve backend migrator to reuse datasource provider and match frontend logic

Co-authored-by: Haris Rozajac <haris.rozajac12@gmail.com>
Co-authored-by: Oscar Kilhed <oscar.kilhed@grafana.com>
Co-authored-by: Stephanie Hingtgen <stephanie.hingtgen@grafana.com>

packages/grafana-schema/src/schema/dashboard/v2alpha1/types.spec.gen.ts

@@ -259,6 +259,8 @@ export interface FieldConfigSource {
 	defaults: FieldConfig;
 	// Overrides are the options applied to specific fields overriding the defaults.
 	overrides: {
+		// Describes config override rules created when interacting with Grafana.
+		__systemRef?: string;
 		matcher: MatcherConfig;
 		properties: DynamicConfigValue[];
 	}[];
@@ -457,7 +459,8 @@ export type ThresholdsMode = "absolute" | "percentage";
 export const defaultThresholdsMode = (): ThresholdsMode => ("absolute");
 
 export interface Threshold {
-	value: number;
+	// Value null means -Infinity
+	value: number | null;
 	color: string;
 }
 

packages/grafana-schema/src/schema/dashboard/v2beta1/types.spec.gen.ts

@@ -162,7 +162,7 @@ export interface PanelQuerySpec {
 
 export const defaultPanelQuerySpec = (): PanelQuerySpec => ({
 	query: defaultDataQueryKind(),
-	refId: "",
+	refId: "A",
 	hidden: false,
 });
 
@@ -266,6 +266,8 @@ export interface FieldConfigSource {
 	defaults: FieldConfig;
 	// Overrides are the options applied to specific fields overriding the defaults.
 	overrides: {
+		// Describes config override rules created when interacting with Grafana.
+		__systemRef?: string;
 		matcher: MatcherConfig;
 		properties: DynamicConfigValue[];
 	}[];
@@ -464,7 +466,8 @@ export type ThresholdsMode = "absolute" | "percentage";
 export const defaultThresholdsMode = (): ThresholdsMode => ("absolute");
 
 export interface Threshold {
-	value: number;
+	// Value null means -Infinity
+	value: number | null;
 	color: string;
 }
 
@@ -1282,7 +1285,7 @@ export interface IntervalVariableSpec {
 	auto: boolean;
 	auto_min: string;
 	auto_count: number;
-	refresh: VariableRefresh;
+	refresh: "onTimeRangeChanged";
 	label?: string;
 	hide: VariableHide;
 	skipUrlSync: boolean;
@@ -1297,7 +1300,7 @@ export const defaultIntervalVariableSpec = (): IntervalVariableSpec => ({
 	auto: false,
 	auto_min: "",
 	auto_count: 0,
-	refresh: "never",
+	refresh: "onTimeRangeChanged",
 	hide: "dontHide",
 	skipUrlSync: false,
 });