Add Azure Spring Apps Enterprise tier

Add Spring Apps Enterprisetier:
- Add bicep template in `core/host` to deploy `AI Shopping Cart Service` to Azure Spring Apps Enterprise tier
- Name of the bicep template: `spring-apps-enterprise.bicep`
- Add a parameter in `main.bicep` to select Spring Apps plan.
- Parameter name: `springAppsPlan`
- Parameter allowed values: `Consumption`, `Standard`, `Enterprise`
- Default value: `Consumption`
- When the value of `springAppsPlan` is Enterprise, the Azure Container Apps environment should not be deployed and the front-end should be deploy to Azure Spring Apps.
- A new YAML file `_enterprise` should be available to deploy the front-end to static web app. This YAML file should be rename to azure.yaml if the enterprise plan needs to be use
- A new `README_enterprise.md` should be available at the root of the repository
- In the root `README.md`/Application Architecture, a link to the enterprise tier readme should be added.
- The setup of the options (environment variable) to choose the plan needs to be described at the end of the quickstart guide and point also to `README_enterprise.md`
- A new Azure DevOps pipeline and a new GitHub workflow should be created for the enterprise plan

> Please provide us with the following information:
> ---------------------------------------------------------------

### This issue is for a: (mark with an `x`)
```
- [ ] bug report -> please search issues before submitting
- [x] feature request
- [ ] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)
```

### Minimal steps to reproduce
> N/A

### Any log messages given by the failure
> N/A

### Expected/desired behavior
> Be able to deploy to Spring Apps Enterprise tier

### Versions
> 1.0.0

### Mention any other details that might be useful

> ---------------------------------------------------------------
> Thanks! We'll be in touch soon.

Beginne mit der Überprüfung des bestehenden Bereitstellungsablaufs in core/host und main.bicep, einschließlich der Auswahl des aktuellen Spring Apps-Plans und der Bereitstellung des Frontends. Sieh dir anschließend die README und die Quickstart-Anleitung des Repositorys an, bevor du das Enterprise-Template, das Deployment-YAML, die Dokumentation, die Azure DevOps-Pipeline und den GitHub-Workflow hinzufügst. Als abgeschlossen gilt die Aufgabe, wenn Enterprise Azure Spring Apps auswählt, die Container Apps-Umgebung vermeidet und alle Bereitstellungs- und Dokumentationspfade beschrieben sind.

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