enhancement: CLI should generate the entities in dab-config using the provided schema file for Cosmos

When we do a dab init, for cosmos db , it is mandatory to provide a schema file as input. The schema file generally contains entities required.
**Current behaviour:**
We need to do a dab add again to add the same entities to the dab-config file.
As gql is case sensitive, there could be errors in casing of entity names between schema file and same entities added using dab add

_Example:_
schema.gql
```
...
type Character @model(name:"Character") {
id : ID,
name : String,
type: String,
homePlanet: Int,
primaryFunction: String
}
...
```
And then possible manual error when we add the same entities to config,
`dab add character ...`

Because of the case difference between `Character` and `character`, the dab engine fails to perform operations.

Note: This is a behavior we have seen occurring commonly, and also got similar feedback from initial customers

**Proposed enhancement:**
- When we input the schema file to the `dab init` command, it should generate the corresponding entities in the dab-config file to avoid manual errors and this also enhances the user experience.