Project Knights Travails: Adding additional information about the Graphs data structure

[PivtoranisV]

Because

It would be great to add more information about the graph data structure in the Knight’s Travails project context so that learners can relate it to the current problem. The current version of the lesson briefly introduces graphs but does not specify how this data structure relates to solving the knight’s movement problem.

This PR

• Added a new part before the Assignment

Issue

Related to #28931

Additional Information

PR for Ruby path for the same project already approved

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