Option to not create the collection when compiling model

### Prerequisites

- [X] I have written a descriptive issue title
- [X] I have searched existing issues to ensure the feature has not already been requested

### 🚀 Feature Proposal

Placing `null` in the collectionName argument should make it not create a collection for that model

### Motivation

_No response_

### Example

`mongoose.model(name, schema, null)`

Start by tracing how mongoose.model(name, schema, null) handles the collectionName argument and where model compilation triggers collection creation. Confirm the expected behavior against the existing model and collection lifecycle tests; done means a null collection name compiles the model without creating a collection.

Written by the indexing model from the issue text.