Providers and Injections should be by name or at least by Map<string,type> and not by a simple Array<type>

### Version info

**Angular:** 14.2

**Firebase:** 9.9.3

**AngularFire:** 7.4.1

**Other (e.g. Ionic/Cordova, Node, browser, operating system):** Irrelevant

### Expected behavior

Provide / Injection by name or Map where the string is the name to find easy and clean your angular firebase components or have a function to findByName(name: string).

I'm not talking only about Auth, I'm talking regarding all your types but I use Auth for the examples

``` typescript
@NgModule({
imports: [
provideFirebaseApp(() => initializeApp(config)), // default app
provideFirebaseApp(() => initializeApp(config2, 'app2')),
provideFirebaseApp(() => initializeApp(config3, 'app3')),
provideAuth(() => getAuth()), // from default app
provideAuth(() => getAuth(getApp('app2'))),
provideAuth(() => getAuth(getApp('app3'))),
],
})
```

One of the next options should be there to be use it easy:

**Option 1** - Could be work with your actual Array but I think that search this search byName in this array is dirty and I recommend to not reinvent the wheel and use a Map
``` typescript
constructor(
private authApp: Auth,
private authApp2: AuthInstances.getByName('app2'),
private authApp3: AuthInstances.getByName('app3'),
) { }
```

**Option 2** - Could be work with your actual Array but again I recommend to not reinvent the wheel and use a Map
``` typescript
constructor(private authInstances: AuthInstances) { }

doWithAuth(name: string) {
const auth = this.authInstances.getByName(name)
// the things that you want to do with your auth
}
```

**Other options** - Any idea that let you select your angular fire element more easy and clean that now.

### Actual behavior

Provide / Injection is a simple Array and does not have any method to select by name.

``` typescript
@NgModule({
imports: [
provideFirebaseApp(() => initializeApp(config)), // default app
provideFirebaseApp(() => initializeApp(config2, 'app2')),
provideFirebaseApp(() => initializeApp(config3, 'app3')),
provideAuth(() => getAuth()), // from default app
provideAuth(() => getAuth(getApp('app2'))),
provideAuth(() => getAuth(getApp('app3'))),
],
})
```

``` typescript
private authMap: Map;
constructor(private authInstances: AuthInstances) {
this.authInstances.forEach(auth => {
this.authMap.set(auth.name,auth);
});
}
```

### Feedback

I think that your Provide / Injection should work with maps or with something that can be select the future injection by name.

Another important thing, is that you must declare a default app, if not the AuthInstaces fail because default app is not initializate and then to find this default app is so ugly `name: "[DEFAULT]"`

To finish, you cannot import only one auth if your auth is not default, because you have a way to import default and to import an array with default and another auths. Is there a way to inject `auth: Auth` by name and avoid import all the array?

Issue post from discussion: _Originally posted by @todosybuenrollo in https://github.com/angular/angularfire/discussions/1026#discussioncomment-3613308_

Inizia tracciando gli entry point provideFirebaseApp, provideAuth e AuthInstances descritti nell’issue, incluso il modo in cui vengono risolte le app Firebase predefinita e con nome. Esamina il comportamento attuale dell’injection e i test correlati, se presenti, prima di decidere tra injection con nome e un’API basata su map. Il lavoro è completato quando i consumer possono selezionare le istanze Auth non predefinite per nome senza dover analizzare manualmente un array, mantenendo il comportamento dell’app predefinita.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.