[QUESTION] How to Inject current request into request scoped provider?
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## Goal
I'm building a multi-tenant SaaS app where each tenant's data is housed in a separate DB.  I'd like to be able to inject a DB connection on a per-request basis.  My thinking here is to consolidate the DB selection logic to avoid polluting the application logic with tenant DB selection logic.  The DB connection will be selected based on the hostname in the request. 


## Current challenge
I have a request scoped provider set up and it currently does execute on every request.  However, I can't seem to figure out how to inject the current request into the factory function.  When inject `PlatformRequest`, it seems to be an object with a `$ctx` property, but everything else under `$ctx` are undefined. 

I've seen a similar example in NestJs where a request scoped provider is able to grab the current request in order to construct a DB connection. I was hoping that something  similar is possible in tsed.

From the docs, I know it's possible to inject context or request into methods using decorators, but that doesn't seem possible here since the factory function is not a method and decorators can't be used here. 

What class or token do I need to specify in the `deps` property in order to get the current request into my factory function?

## Example

```ts
registerProvider({
    provide: CONNECTION,
    scope: ProviderScope.REQUEST,
    type: ProviderType.FACTORY,
    useFactory (req: PlatformRequest) {
        console.log('creating DB connection');

        // TODO: how do we get the request context injected here?

        return  someDbConnections;
    },
    deps: [PlatformRequest]
});

```

## Acceptance criteria

- [ ] Ability to inject request context into a request scoped provider


## Information

- **Version:** 6.121.1
- Packages: 