Model: AppConfiguration model supports Ingress resource

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What would you like to be added?

Support native Ingress resource in AppConfiguration model. This includes:

• Definition of front-end (customer-facing) model
• Upgrade the corresponding back-end render logic
• Support for the most popular ingress controllers
• Documentation updated to reflect the new front-end (customer-facing) model: The kinds of ingress controller kusion supports, how to use the new model, with all the fields and possible values

Why is this needed?

This is part of the upgrade to AppConfiguration model. This enables kusion to render a Kubernetes ingress based on user input and supports the transition from the current Server model to AppConfiguration model.

Acceptance Criteria

Kusion can properly produce a valid, rendered YAML containing an ingress, based on the user input from the accessory section in the AppConfiguration model. Documentations updated on Kusionstack.io.