feat: add integration tests (#6923)

### Summary

This PR introduces several integration tests, a mix of manually written
tests and those generated using the `generate-integration-tests` Python
script located in the `scripts` folder.

### Tests Added:
- **Authentication tests**: Validating login, registration, and token
handling.
- **FindMany queries**: Fetching multiple records for all existing
entities that do not require input arguments.

### How the Integration Tests Work:
- A `setupTest` function is called during the Jest test run. This
function initializes a test instance of the application and exposes it
on a dedicated port.
- Since tests are executed in isolated workers, they do not have direct
access to the in-memory app instance. Instead, the tests query the
application through the exposed port.
- A static accessToken is used, this one as a big expiration time so it
will never expire (365 years)
- The queries are executed, and the results are validated against
expected outcomes.

### Current State and Next Steps:
- These tests currently run using the existing development seed data. We
plan to introduce more comprehensive test data using `faker` to improve
coverage.
- At the moment, the only mutation tests implemented are for
authentication. Future updates should include broader mutation testing
for other entities.

---------

Co-authored-by: Charles Bochet <charles@twenty.com>

packages/twenty-server/src/engine/core-modules/environment/environment.module.ts

@@ -1,9 +1,9 @@
 import { Global, Module } from '@nestjs/common';
 import { ConfigModule } from '@nestjs/config';
 
-import { EnvironmentService } from 'src/engine/core-modules/environment/environment.service';
-import { ConfigurableModuleClass } from 'src/engine/core-modules/environment/environment.module-definition';
 import { validate } from 'src/engine/core-modules/environment/environment-variables';
+import { ConfigurableModuleClass } from 'src/engine/core-modules/environment/environment.module-definition';
+import { EnvironmentService } from 'src/engine/core-modules/environment/environment.service';
 
 @Global()
 @Module({
@@ -12,6 +12,7 @@ import { validate } from 'src/engine/core-modules/environment/environment-variab
       isGlobal: true,
       expandVariables: true,
       validate,
+      envFilePath: process.env.NODE_ENV === 'test' ? '.env.test' : '.env',
     }),
   ],
   providers: [EnvironmentService],

packages/twenty-server/src/engine/core-modules/environment/interfaces/node-environment.interface.ts

@@ -1,4 +1,5 @@
 export enum NodeEnvironment {
+  test = 'test',
   development = 'development',
   production = 'production',
 }