Add start_delay to ActivityOptions for update support

openapi/openapiv2.json

@@ -13632,6 +13632,10 @@
         "priority": {
           "$ref": "#/definitions/v1Priority",
           "description": "Priority metadata. If this message is not present, or any fields are not\npresent, they inherit the values from the workflow."
+        },
+        "startDelay": {
+          "type": "string",
+          "description": "Time to wait before dispatching the first activity task. This delay is not applied to retry attempts.\nWhen updated, anchored to the original `schedule_time`. If the resulting time is in the past, dispatches\nimmediately."
         }
       }
     },

openapi/openapiv3.yaml

@@ -9997,6 +9997,13 @@ components:
           description: |-
             Priority metadata. If this message is not present, or any fields are not
              present, they inherit the values from the workflow.
+        startDelay:
+          pattern: ^-?(?:0|[1-9][0-9]{0,11})(?:\.[0-9]{1,9})?s$
+          type: string
+          description: |-
+            Time to wait before dispatching the first activity task. This delay is not applied to retry attempts.
+             When updated, anchored to the original `schedule_time`. If the resulting time is in the past, dispatches
+             immediately.
     ActivityPropertiesModifiedExternallyEventAttributes:
       type: object
       properties:

temporal/api/activity/v1/message.proto

@@ -63,6 +63,11 @@ message ActivityOptions {
     // Priority metadata. If this message is not present, or any fields are not
     // present, they inherit the values from the workflow.
     temporal.api.common.v1.Priority priority = 7;
+
+    // Time to wait before dispatching the first activity task. This delay is not applied to retry attempts.
+    // When updated, anchored to the original `schedule_time`. If the resulting time is in the past, dispatches
+    // immediately.
+    google.protobuf.Duration start_delay = 8;
 }
 
 // Information about a standalone activity.