Add default relation to standard object on custom object in manifest (#18033)

add default relation fields when creating an object from an application

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Co-authored-by: prastoin <paul@twenty.com>

packages/twenty-server/src/engine/metadata-modules/logic-function/constants/handler.contant.ts

@@ -1,3 +1,8 @@
 export const DEFAULT_BUILT_HANDLER_PATH = 'src/index.mjs';
 export const DEFAULT_SOURCE_HANDLER_PATH = 'src/index.ts';
 export const DEFAULT_HANDLER_NAME = 'main';
+
+// Matches a valid JS identifier or dotted member expression
+// e.g. "main", "handler", "default.config.handler", "exports.run"
+export const HANDLER_NAME_REGEX =
+  /^[a-zA-Z_$][a-zA-Z0-9_$]*(\.[a-zA-Z_$][a-zA-Z0-9_$]*)*$/;