Model: AppConfiguration model supports Job resource

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What would you like to be added?

Support native Job resource in AppConfiguration model. This includes:

• Definition of front-end (customer-facing) model
• Upgrade the corresponding back-end render logic
• Documentation updated to reflect the new front-end (customer-facing) model: 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 job 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 a job, based on the user input from the workload section in the AppConfiguration model.
Documentations updated on Kusionstack.io.