Adds shadowed 1-1

Why is this change being made?

I went looking for a description of the structure of @sytses' shadowed one on ones but couldn't find it. I felt like this was the best place for this information. I've added the description from my recollection of attending Sid's one on ones during my time in the CEO Shadow program.

Author Checklist

• Correct MR template applied (e.g blog post)
• Provided a concise title for the MR
• Added a description to this MR explaining the reasons for the proposed change, per say-why-not-just-what
• Assign this change to the correct DRI
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