feat: add telemetry to the TemplateElement to detect how long hydration has taken

[janechu]

🙋 Feature Request

Currently it is difficult to know how long hydration is taking, for tracking performance we should have a method to know when hydration has been achieved on any particular FASTElement as well as when hydration has been fully resolved.

Requirements

• Use either a custom element or performance mark
• This should only exist in the debug build

[radium-v]

This should be doable now that #7171 is complete.