Create Telemetry.md (#586)

* Create Telemetry.md

* Fix typo

Author: baronfel

docs/Telemetry.md

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+# Telemetry reporting in the .NET SDK Container tools
+
+Starting in .NET SDK 8.0.400, the Container tooling collects and sends usage telemetry about how the tools are used.
+This is in addition to the [telemetry sent by the CLI](https://learn.microsoft.com/en-us/dotnet/core/tools/telemetry), but uses the same mechanisms and, importantly, adheres to the same [opt-out](https://learn.microsoft.com/en-us/dotnet/core/tools/telemetry#how-to-opt-out) controls.
+
+The telemetry we gather is intended to be general in nature and not leak any personal information - we intend to use this telemetry to help us measure
+* usage of the SDK Containerization feature overall
+* success and failure rates, along with general information about what kinds of failures happen most frequently
+* usage of specific features of the tech, like publishing to various registry kinds, or how the publish was invoked
+
+## Inference telemetry
+
+We log the following information about how the base image inference process occcurred:
+
+| Data Point | Explanation | Sample value |
+| - | - | - |
+| InferencePerformed | If users are manually specifying base images vs making use of inference. | true |
+| TargetFramework | The TargetFramework chosen when doing base image inference. | net8.0 |
+| BaseImage | The value of the base image chosen, but only if that base image is one of the Microsoft-produced images. If a user specifies any image other than the Microsoft-produced images on mcr.microsoft.com, this value is null. | mcr.microsoft.com/dotnet/aspnet | 
+| BaseImageTag | The value of the tag chosen, but only if that tag is for one of the Microsoft-produced images. If a user specifies any image other than the Microsoft-produced images on mcr.microsoft.com, this value is null. | 8.0 |
+| ContainerFamily | The value of the `ContainerFamily` property if a user used the ContainerFamily feature to pick a 'flavor' of one of our base images. This is only set if the user picked or inferred one of the Microsoft-produced .NET images from mcr.microsoft.com | jammy-chiseled |
+| ProjectType | What kind of project was containerized | AspNetCore or Console |
+| PublishMode | How the application was packaged | Aot, Trimmed, SelfContained, or FrameworkDependent |
+| IsInvariant | If the image chosen requires invariant globalization or the user opted into it manually | true |
+| TargetRuntime | The RID that this application was published for | linux-x64 |
+
+## Image creation telemetry
+
+We log the following information about how the container creation and publishing process occurred:
+
+| Data Point | Explanation | Sample value |
+| - | - | - |
+| RemotePullType | If the base image came from a remote registry, what kind of registry was it? |  Azure, AWS, Google, GitHub, DockerHub, MRC, or Other |
+| LocalPullType | If the base image came from a local source, like a container daemon or a tarball. Note - the container tools currently do not support using local sources for base images, this information is added looking forward to that future feature. | Docker, Podman, Tarball | 
+| RemotePushType | If the image was pushed to a remote registry, what kind of registry was it? |   Azure, AWS, Google, GitHub, DockerHub, MRC, or Other |
+| LocalPushType | If the image was pushed to a local destination, what was it? | Docker, Podman, Tarball |
+
+In addition, if various kinds of errors occur during the process we collect data about what kind of error it was:
+
+| Data Point | Explanation | Sample value |
+| - | - | - |
+| Error | The kind of error that occurred | unknown_repository, credential_failure, rid_mismatch, local_load - there are more kinds of errors but we expect the kinds to grow over time |
+| Direction | If the error is a credential_failure, was it to the push or pull registry? | push |
+| Target RID | If the error was a rid_mismatch, what RID was requested | linux-x64 |
+| Available RIDs | If the error was a rid_mismatch, what RIDs did the base image support? | linux-x64,linux-arm64 |