Add Validation for Dispatch Class in Web Application Settings

1️⃣ Description of the idea

Enhance the web application creation process by adding a validation step for the Dispatch Class field. The system should verify that the specified dispatch class exists and is accessible before allowing the web application configuration to be saved. If the class does not exist, the user should receive a clear, informative error message explaining the issue.

2️⃣ Who is the target audience?

Developers configuring new web applications and managing web application setups

3️⃣ What problem does it solve?

Unexpected runtime failures and Poor user experience during app setup

Adding validation prevents these issues by catching errors early during configuration.

4️⃣ How does this impact the efficiency, stability, reliability, etc., of the product?

Ensures web applications are correctly configured before deployment and Lowers support burden related to misconfigured applications

5️⃣ Provide a specific use case or scenario that illustrates how this idea could be used in practice

Current Behavior:

The app saves successfully, but when accessed, it throws a runtime error because the class does not exist, causing confusion and requiring debugging.

With Validation:
Upon saving, the system checks the dispatch class existence, detects the typo, and displays an error message like Dispatch class 'MyApp.DispatchHandler' not found. Please verify the class name before saving.

This prevents saving the invalid configuration and guides the user to correct the mistake immediately.