Feature Request: make documentation about usage of libraries consistent and accurate

### Checklist before submitting a feature request

- [X] I've updated to the latest released version of the SDK
- [X] I've searched for existing [Github issues](https://github.com/facebook/facebook-ios-sdk/issues)
- [X] I've read the [Code of Conduct](https://github.com/facebook/facebook-ios-sdk/blob/main/CODE_OF_CONDUCT.md)

### Goals

Be more consistent, specific, unambiguous and clear about the usage of different libraries.

### Expected results

I think the documentation is a little bit ambiguous, unclear and not always consistent about the usage of the different available FB libraries.

## Part 1: installation of SDKs

I found the following references:
1. https://github.com/facebookarchive/facebook-swift-sdk/blob/master/Announcement.md
2. https://github.com/facebookarchive/facebook-swift-sdk/blob/master/MigrationGuide.md
3. https://cocoapods.org/pods/FacebookSDK
4. https://cocoapods.org/pods/FacebookCore
5. https://cocoapods.org/pods/FBSDKCoreKit
6. https://developers.facebook.com/docs/app-events/upgrade-guide

###### 1. https://github.com/facebookarchive/facebook-swift-sdk/blob/master/Announcement.md
This page may lead to some confusion, but that might be okay, considering the placement and date,

###### 2. https://github.com/facebookarchive/facebook-swift-sdk/blob/master/MigrationGuide.md
Has probably the most accurate description of all pages mentioned here.

###### 3. https://cocoapods.org/pods/FacebookSDK
Is also fairly accurate. Except that the wording

> For projects that include Swift, use `FacebookCore`, `FacebookLogin`, and `FacebookShare`

can be quite confusing. Because if you're not using SPM, but CocoaPods for example, you cannot use this, but you'll have to use the `FBSDKCore` SDK instead. Admittedly, technically, it might be correct, because it is mentioned under the label "SPM", but it's easy to get that part wrong. So I think that can be phrased better.

###### 4. https://cocoapods.org/pods/FacebookCore
On this page it should probably be mentioned that the usage of this package through CocoaPods is deprecated

###### 5. https://cocoapods.org/pods/FBSDKCoreKit
IMO, ideally the explanation on this page should be consistent with `#3`.

###### 6. https://developers.facebook.com/docs/app-events/upgrade-guide
The information on this page is just plain wrong as far as I understood from the rest of the docs. First off, it does not mention SPM at all. Moreover, it mentions to install the`FacebookSDK` SDK through CocoaPods, which does not work (or at the very least causes trouble to your code/build).

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## Part 2: API reference docs

In several places references are made to the API reference on this URL: https://developers.facebook.com/docs/ios/reference_obj-c

There are a few problems with that page in my eyes:

1. Bit nit-picky but: the URL itself is a bit misleading, because it is actually the reference for both Swift and Obj C (because they're the same package now).
2. The first URL on that page is broken ([FBSDKCoreKit](https://developers.facebook.com/docs/reference/iossdk/current/FBSDKCoreKit/))
3. The reference mentions "FBSDK*" (e.g. "FBSDKCoreKit"). But if you're coming from a page that mentions to install the `FacebookCore` SDK, that's pretty confusing.

### Code samples & details

_No response_