Relative run mode (#1512)

* inti relative mode

* send imediat update on mode change

* add relative to test

* don't persist offset mode

* add test relative and update calc function

* pass data from ssocket

* add dev guard

* spelling and comments

* show relative in offset overview

* remove comments

* refactor: move totalDelay to _rundown

* update  clear naming and comments

* remove old testing values

apps/server/src/api-integration/integration.controller.ts

@@ -1,4 +1,4 @@
-import { MessageState, OntimeEvent, SimpleDirection, SimplePlayback } from 'ontime-types';
+import { MessageState, OffsetMode, OntimeEvent, SimpleDirection, SimplePlayback } from 'ontime-types';
 import { MILLIS_PER_HOUR, MILLIS_PER_SECOND } from 'ontime-utils';
 
 import { DeepPartial } from 'ts-essentials';
@@ -17,6 +17,7 @@ import { throttle } from '../utils/throttle.js';
 import { willCauseRegeneration } from '../services/rundown-service/rundownCacheUtils.js';
 
 import { handleLegacyMessageConversion } from './integration.legacy.js';
+import { coerceEnum } from '../utils/coerceType.js';
 
 const throttledUpdateEvent = throttle(updateEvent, 20);
 let lastRequest: Date | null = null;
@@ -286,6 +287,11 @@ const actionHandlers: Record<string, ActionHandler> = {
 
     throw new Error('No matching method provided');
   },
+  offsetmode: (payload) => {
+    const mode = coerceEnum<OffsetMode>(payload, OffsetMode);
+    runtimeService.setOffsetMode(mode);
+    return { payload: 'success' };
+  },
 };
 
 /**