Update onboarding v2 credit reward amounts (#22399)

Adjusts the free-credit rewards shown and granted across onboarding v2:

- Import contacts: 2 → 1 credit
- Install app: 1 → 0.5 credit per app
- Invite user: 0.5 credit per user (unchanged)
- Upgrade free trial: 5 → 1 credit

All values live as defaults in `config-variables.ts` (micro-credits) and
reach the frontend via ClientConfig, so nothing else needed changing.

Note: the upgrade reward maps to
`BILLING_FREE_WORKFLOW_CREDITS_FOR_TRIAL_PERIOD_WITH_CREDIT_CARD`, which
is also the actual with-credit-card trial grant, so that grant drops
from 5 → 1 credit too (intentionally the same number the onboarding
advertises).

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packages/twenty-server/src/engine/core-modules/twenty-config/config-variables.ts

@@ -862,7 +862,7 @@ export class ConfigVariables {
   })
   @CastToPositiveNumber()
   @ValidateIf((env) => env.IS_BILLING_ENABLED === true)
-  BILLING_FREE_WORKFLOW_CREDITS_FOR_TRIAL_PERIOD_WITH_CREDIT_CARD = 5_000_000;
+  BILLING_FREE_WORKFLOW_CREDITS_FOR_TRIAL_PERIOD_WITH_CREDIT_CARD = 1_000_000;
 
   @ConfigVariablesMetadata({
     group: ConfigVariablesGroup.BILLING_CONFIG,
@@ -942,7 +942,7 @@ export class ConfigVariables {
   @CastToPositiveNumber()
   @IsInt()
   @IsOptional()
-  ONBOARDING_IMPORT_CONTACTS_CREDITS_REWARD = 2_000_000;
+  ONBOARDING_IMPORT_CONTACTS_CREDITS_REWARD = 1_000_000;
 
   @ConfigVariablesMetadata({
     group: ConfigVariablesGroup.BILLING_CONFIG,
@@ -975,7 +975,7 @@ export class ConfigVariables {
   @CastToPositiveNumber()
   @IsInt()
   @IsOptional()
-  ONBOARDING_INSTALL_APPS_CREDITS_REWARD_PER_APP = 1_000_000;
+  ONBOARDING_INSTALL_APPS_CREDITS_REWARD_PER_APP = 500_000;
 
   @ConfigVariablesMetadata({
     group: ConfigVariablesGroup.SERVER_CONFIG,