Schema v2: Move annotation mappings out of legacyOptions (#114721)

* Add mappings property to v2(alpha/beta)1

* Mappings convetions

* OpenAPI spec

* fe annotaations mapping

* Update snapshots

* v2->v1 conversion

* fix tests

---------

Co-authored-by: Haris Rozajac <haris.rozajac12@gmail.com>

pkg/tests/apis/openapi_snapshots/dashboard.grafana.app-v2alpha1.json

@@ -1275,6 +1275,24 @@
           }
         }
       },
+      "com.github.grafana.grafana.apps.dashboard.pkg.apis.dashboard.v2alpha1.DashboardAnnotationEventFieldMapping": {
+        "description": "Annotation event field mapping. Defines how to map a data frame field to an annotation event field.",
+        "type": "object",
+        "properties": {
+          "regex": {
+            "description": "Regular expression to apply to the field value",
+            "type": "string"
+          },
+          "source": {
+            "description": "Source type for the field value",
+            "type": "string"
+          },
+          "value": {
+            "description": "Constant value to use when source is \"text\"",
+            "type": "string"
+          }
+        }
+      },
       "com.github.grafana.grafana.apps.dashboard.pkg.apis.dashboard.v2alpha1.DashboardAnnotationPanelFilter": {
         "type": "object",
         "required": [
@@ -1354,6 +1372,18 @@
               "type": "object"
             }
           },
+          "mappings": {
+            "description": "Mappings define how to convert data frame fields to annotation event fields.",
+            "type": "object",
+            "additionalProperties": {
+              "default": {},
+              "allOf": [
+                {
+                  "$ref": "#/components/schemas/com.github.grafana.grafana.apps.dashboard.pkg.apis.dashboard.v2alpha1.DashboardAnnotationEventFieldMapping"
+                }
+              ]
+            }
+          },
           "name": {
             "type": "string",
             "default": ""