Extend service invocation to non-Dapr endpoints

[dapr-bot]

This issue was automatically created by Dapr Bot because a "docs-needed" label was added to dapr/dapr#4549.

TODO: Add more details as per this template.

[sicoyle]

/assign

[msfussell]

Update the following doc topics

• Update - https://docs.dapr.io/developing-applications/building-blocks/service-invocation/service-invocation-overview/ need to describe the overview of the feature and when to use this
• New - How to: Invoke non-Dapr services using HTTP. Needs to have a diagram included to show the contrast with service invocation with AppId. Need to describe the precedence order of named HttpResource->HTTP URL path->AppId
• Update - https://docs.dapr.io/reference/api/service_invocation_api/
• Update - https://docs.dapr.io/developing-applications/building-blocks/bindings/howto-bindings/ - Add a note here about invoke being the best way to call methods on external services
• Update - https://docs.dapr.io/reference/components-reference/supported-bindings/http/ - Add a note here about invoke being the best way to call methods on external services.
• Update - Preview features https://docs.dapr.io/operations/support/support-preview-features/
• New - Add under Reference/Spec the schema definition for the HttpEndpoint spec and what it can contain.
• Update - https://docs.dapr.io/reference/api/metadata_api/ to include the list of named HttpEndpoints that are loaded.
• Update - HttpEndpoint in terminology https://docs.dapr.io/concepts/terminology/

[sicoyle]

@msfussell Can we mark this as closed since the PR has been merged adding docs?

[msfussell]

Completed