Protect against ODE when accessing configuration providers

[tarekgh]

Fixes #117491

[Copilot]

Pull Request Overview

This PR adds protection against ObjectDisposedException when iterating through configuration providers, ensuring disposed providers are skipped instead of propagating exceptions.

• Wraps the provider.TryGet call in a try/catch for ObjectDisposedException
• Adds explanatory comments for skipping disposed providers

Comments suppressed due to low confidence (2)

src/libraries/Microsoft.Extensions.Configuration/src/InternalConfigurationRootExtensions.cs:55

• Add a unit test that disposes a provider mid-enumeration to verify that ObjectDisposedException is correctly caught and the provider is skipped.

                try

src/libraries/Microsoft.Extensions.Configuration/src/InternalConfigurationRootExtensions.cs:51

• Iterating directly over the providers list while it can be mutated by ConfigurationManager may lead to an InvalidOperationException. Consider capturing a snapshot (e.g., var snapshot = providers.ToList()) before the loop to avoid collection modification issues.

            for (int i = providers.Count - 1; i >= 0; i--)