fix: add missing displayName and slug to organization reducer (#40779)

## Description
Fixes a bug where the organization's `displayName` and `slug` fields
were not being properly stored in the Redux state when fetching the
current organization configuration.

## Changes
- Added `displayName` and `slug` fields to the
`FETCH_CURRENT_ORGANIZATION_CONFIG_SUCCESS` reducer handler
- These fields were already defined in the `OrganizationReduxState`
interface but were missing from the actual state update

## Automation

/ok-to-test tags="@tag.Sanity"

### 🔍 Cypress test results
<!-- This is an auto-generated comment: Cypress test results  -->
> [!TIP]
> 🟢 🟢 🟢 All cypress tests have passed! 🎉 🎉 🎉
> Workflow run:
<https://github.com/appsmithorg/appsmith/actions/runs/15286413781>
> Commit: cca1886b0d8dd24a9193dab5a0a5a7a3c004cda2
> <a
href="https://internal.appsmith.com/app/cypress-dashboard/rundetails-65890b3c81d7400d08fa9ee5?branch=master&workflowId=15286413781&attempt=1"
target="_blank">Cypress dashboard</a>.
> Tags: `@tag.Sanity`
> Spec:
> <hr>Tue, 27 May 2025 22:31:26 UTC
<!-- end of auto-generated comment: Cypress test results  -->


## Communication
Should the DevRel and Marketing teams inform users about this change?
- [ ] Yes
- [ ] No


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **New Features**
- Organization details now display additional information, including
display name and slug, when viewing organization configuration.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

app/client/src/ce/reducers/organizationReducer.ts

@@ -74,6 +74,8 @@ export const handlers = {
         ...action.payload.organizationConfiguration.brandColors,
       },
     },
+    displayName: action.payload.displayName,
+    slug: action.payload.slug,
     isLoading: false,
     instanceId: action.payload.instanceId,
     tenantId: action.payload.tenantId,