Improve performance on metadata computation (#12785)

In this PR:

## Improve recompute metadata cache performance. We are aiming for
~100ms

Deleting relationMetadata table and FKs pointing on it
Fetching indexMetadata and indexFieldMetadata in a separate query as
typeorm is suboptimizing

## Remove caching lock

As recomputing the metadata cache is lighter, we try to stop preventing
multiple concurrent computations. This also simplifies interfaces

## Introduce self recovery mecanisms to recompute cache automatically if
corrupted

Aka getFreshObjectMetadataMaps

## custom object resolver performance improvement:  1sec to 200ms

Double check queries and indexes used while creating a custom object
Remove the queries to db to use the cached objectMetadataMap

## reduce objectMetadataMaps to 500kb
<img width="222" alt="image"
src="https://github.com/user-attachments/assets/2370dc80-49b6-4b63-8d5e-30c5ebdaa062"
/>

We used to stored 3 fieldMetadataMaps (byId, byName, byJoinColumnName).
While this is great for devXP, this is not great for performances.
Using the same mecanisme as for objectMetadataMap: we only keep byIdMap
and introduce two otherMaps to idByName, idByJoinColumnName to make the
bridge

## Add dataloader on IndexMetadata (aka indexMetadataList in the API)

## Improve field resolver performances too

## Deprecate ClientConfig

packages/twenty-server/src/engine/api/graphql/workspace-query-runner/utils/graphql-query-runner-exception-handler.util.ts

@@ -28,6 +28,7 @@ export const graphqlQueryRunnerExceptionHandler = (
     case GraphqlQueryRunnerExceptionCode.RELATION_SETTINGS_NOT_FOUND:
     case GraphqlQueryRunnerExceptionCode.RELATION_TARGET_OBJECT_METADATA_NOT_FOUND:
     case GraphqlQueryRunnerExceptionCode.INVALID_POST_HOOK_PAYLOAD:
+    case GraphqlQueryRunnerExceptionCode.MISSING_SYSTEM_FIELD:
       throw error;
     default: {
       const _exhaustiveCheck: never = error.code;

packages/twenty-server/src/engine/api/graphql/workspace-query-runner/utils/handle-duplicate-key-error.util.ts

@@ -1,5 +1,5 @@
-import { QueryFailedError } from 'typeorm';
 import { isDefined } from 'twenty-shared/utils';
+import { QueryFailedError } from 'typeorm';
 
 import { WorkspaceQueryRunnerOptions } from 'src/engine/api/graphql/workspace-query-runner/interfaces/query-runner-option.interface';
 
@@ -14,14 +14,14 @@ export const handleDuplicateKeyError = (
   if (indexNameMatch) {
     const indexName = indexNameMatch[1];
 
-    const deletedAtFieldMetadata =
-      context.objectMetadataItemWithFieldMaps.fieldsByName['deletedAt'];
+    const deletedAtFieldMetadataId =
+      context.objectMetadataItemWithFieldMaps.fieldIdByName['deletedAt'];
 
     const affectedColumns =
       context.objectMetadataItemWithFieldMaps.indexMetadatas
         .find((index) => index.name === indexName)
         ?.indexFieldMetadatas?.filter(
-          (field) => field.fieldMetadataId !== deletedAtFieldMetadata?.id,
+          (field) => field.fieldMetadataId !== deletedAtFieldMetadataId,
         )
         .map((indexField) => {
           const fieldMetadata =