fix(core-dsr): flip processingRestrictedAt in soft-delete for self role

PayloadDataDelete.deleteSubjectData('soft') was NULLing PII fields and
emitting RESTRICT audit entries, but never setting processingRestrictedAt
on self-kind rows — violating GDPR Art. 17 restriction semantics.

softRedactOwnerRows now accepts optional extraData; processOwnerRows
passes { processingRestrictedAt: new Date().toISOString() } when
kind === 'self' and mode === 'soft'. Owner-kind rows are intentionally
excluded (restriction flag belongs on the subject record, not owned rows).

Added two dedicated tests: one asserting the field is present for self,
one asserting it is absent for owner.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/core-dsr/src/__tests__/payload-data-delete.test.ts

@@ -56,7 +56,7 @@ describe("PayloadDataDelete", () => {
       expect(mockPayload.update).toHaveBeenCalledWith({
         collection: "users",
         id: "alice",
-        data: { email: null, name: null },
+        data: expect.objectContaining({ email: null, name: null }),
         overrideAccess: true,
       });
 
@@ -70,6 +70,59 @@ describe("PayloadDataDelete", () => {
       });
     });
 
+    it("self role: sets processingRestrictedAt in the update call", async () => {
+      const config = makeMockConfig([
+        {
+          slug: "users",
+          custom: {
+            subject: { field: "id", kind: "self" },
+            pii: { email: { exportable: true } },
+          },
+        },
+      ]);
+
+      mockPayload.find.mockResolvedValue({
+        docs: [{ id: "alice", email: "a@ex.com" }],
+      });
+
+      const deleter = new PayloadDataDelete(config, auditLog, mockGetPayload);
+      await deleter.deleteSubjectData("alice", "soft");
+
+      expect(mockPayload.update).toHaveBeenCalledWith(
+        expect.objectContaining({
+          data: expect.objectContaining({
+            processingRestrictedAt: expect.any(String),
+          }),
+        }),
+      );
+    });
+
+    it("owner role: does NOT set processingRestrictedAt", async () => {
+      const config = makeMockConfig([
+        {
+          slug: "orders",
+          custom: {
+            subject: { field: "userId", kind: "owner" },
+            pii: { shippingAddress: { exportable: true } },
+          },
+        },
+      ]);
+
+      mockPayload.find.mockResolvedValue({
+        docs: [{ id: "o-1", userId: "alice", shippingAddress: "1 Main" }],
+      });
+
+      const deleter = new PayloadDataDelete(config, auditLog, mockGetPayload);
+      await deleter.deleteSubjectData("alice", "soft");
+
+      expect(mockPayload.update).toHaveBeenCalledWith({
+        collection: "orders",
+        id: "o-1",
+        data: { shippingAddress: null },
+        overrideAccess: true,
+      });
+    });
+
     it("happy path — owner role: NULLs exportable fields in owned rows", async () => {
       const config = makeMockConfig([
         {