FlatObjectMetadataMaps and non FP style refactor (#13590)

# Introduction
- Retrieveing flat-object-metadata-maps for input transpilation, we
decided not to introduce map merge for remaining validation operation
for the moment
- Refactored the field metadata service v2 to sequentially
optimistically render on each iteration

packages/twenty-shared/src/utils/fromArrayToValuesByKeyRecord.util.ts

@@ -0,0 +1,27 @@
+import { StringPropertyKeys } from '@/utils/trim-and-remove-duplicated-whitespaces-from-object-string-properties';
+import { isDefined } from '@/utils/validation';
+
+export const fromArrayToValuesByKeyRecord = <T extends object>({
+  array,
+  key,
+}: {
+  array: T[];
+  key: StringPropertyKeys<T>;
+}) => {
+  return array.reduce<Record<string, T[]>>((acc, value) => {
+    const computedKey = value[key] as string;
+    const occurrence = acc[computedKey];
+
+    if (isDefined(occurrence)) {
+      return {
+        ...acc,
+        [computedKey]: [...occurrence, value],
+      };
+    }
+
+    return {
+      ...acc,
+      [computedKey]: [value],
+    };
+  }, {});
+};