feat: finish mockups with small improvements

docs/src/report.md

@@ -16,6 +16,9 @@ todo: document other OS
 ## Mockups
 ## Case study with the classic experience
 Let's consider a typical coding exercise that David needs to resolve:  
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+---
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 #### Dog message
 Write a small program that displays this message built with the first 2 args. You don't need to check the second arg to be a number.
 
@@ -67,6 +70,8 @@ This workflow resume all different steps that David performs until he finish the
 
 Let's consider a struct exercise that Alice needs to resolve:  
 
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 #### 2. Basic dog struct
 
 Write a basic dog structure with a name and legs number. Print given dog with first 2 args. If `-n` ask to define a new dog, and if `-s` show the size of the struct.