Modify and snap to circle in user coordinates

Correct modify interaction at center and at drawn circle circumference
Correct snap interaction at drawn circle circumference

Test circle geometry in a user projection

src/ol/interaction/Snap.js

@@ -14,7 +14,7 @@ import PointerInteraction from './Pointer.js';
 import {getValues} from '../obj.js';
 import VectorEventType from '../source/VectorEventType.js';
 import RBush from '../structs/RBush.js';
-import {fromUserCoordinate, toUserCoordinate} from '../proj.js';
+import {getUserProjection, fromUserCoordinate, toUserCoordinate} from '../proj.js';
 
 
 /**
@@ -431,8 +431,13 @@ class Snap extends PointerInteraction {
     } else if (this.edge_) {
       const isCircle = closestSegmentData.feature.getGeometry().getType() === GeometryType.CIRCLE;
       if (isCircle) {
-        vertex = closestOnCircle(pixelCoordinate,
-          /** @type {import("../geom/Circle.js").default} */ (closestSegmentData.feature.getGeometry()));
+        let circleGeometry = closestSegmentData.feature.getGeometry();
+        const userProjection = getUserProjection();
+        if (userProjection) {
+          circleGeometry = circleGeometry.clone().transform(userProjection, projection);
+        }
+        vertex = toUserCoordinate(closestOnCircle(projectedCoordinate,
+          /** @type {import("../geom/Circle.js").default} */ (circleGeometry)), projection);
       } else {
         tempSegment[0] = fromUserCoordinate(closestSegment[0], projection);
         tempSegment[1] = fromUserCoordinate(closestSegment[1], projection);
@@ -482,7 +487,16 @@ class Snap extends PointerInteraction {
    * @private
    */
   writeCircleGeometry_(feature, geometry) {
-    const polygon = fromCircle(geometry);
+    const projection = this.getMap().getView().getProjection();
+    let circleGeometry = geometry;
+    const userProjection = getUserProjection();
+    if (userProjection) {
+      circleGeometry = /** @type {import("../geom/Circle.js").default} */ (circleGeometry.clone().transform(userProjection, projection));
+    }
+    const polygon = fromCircle(circleGeometry);
+    if (userProjection) {
+      polygon.transform(projection, userProjection);
+    }
     const coordinates = polygon.getCoordinates()[0];
     for (let i = 0, ii = coordinates.length - 1; i < ii; ++i) {
       const segment = coordinates.slice(i, i + 2);