What: Add TOC due diligence guide and supporting templates

[TheFoxAtWork]

Why:

• Align TOC processes with recommendations from the moving levels task force

This change address the need by:

• Creating the needed templates
• creating the dd-toc-guide.md
• updating the onboarding to link to the dd-toc-guide.md

DO NOT MERGE UNTIL AFTER #1234

Signed-off-by: Emily Fox themoxiefoxatwork@gmail.com

[TheFoxAtWork]

This PR is replaced by #1263