[release/8.0] Add doc for the new invoker classes

[github-actions]

Backport of #90536 to release/8.0

/cc @steveharter

Customer Impact

New doc for new v8 feature.

Testing

NA

Risk

NA

IMPORTANT: If this backport is for a servicing release, please verify that:

• The PR target branch is release/X.0-staging, not release/X.0.

• If the change touches code that ships in a NuGet package, you have added the necessary package authoring and gotten it explicitly reviewed.

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Issue Details

---

Backport of #90536 to release/8.0

/cc @steveharter

Customer Impact

Testing

Risk

IMPORTANT: If this backport is for a servicing release, please verify that:

• The PR target branch is release/X.0-staging, not release/X.0.

• If the change touches code that ships in a NuGet package, you have added the necessary package authoring and gotten it explicitly reviewed.

Author:	github-actions[bot]
Assignees:	-
Labels:	area-System.Reflection
Milestone:	-

[carlossanlop]

@steveharter this PR is targeting release/8.0, which is RC2. Was that your intention?

If not, then please retarget this PR to release/8.0-rc1. Once you merge this, the bot will automatically send it to release/8.0 for you.

[buyaa-n]

this PR is targeting release/8.0, which is RC2. Was that your intention?

Yes, it is for RC2

[carlossanlop]

@buyaa-n let me know when the CI is done in the latest re-run. Don't press the "Update branch" button, or the CI will restart. If you ping me, I can bypass the restriction and merge the PR for you (if it's ready to merge).

[carlossanlop]

Oh I see, this PR is all documentation. Can you please also port these docs to dotnet-api-docs using the PortToDocs.exe tool from dotnet/api-docs-sync ? This needs to be done before the RC2 snap so that we include it in GA.

[steveharter]

Doc port: dotnet/dotnet-api-docs#9194