docs(README): minor changes to README.md

[ItsMeBrille]

Minor changes to README.md

• Fixed sentences and minor spelling for better first impression of the project
• Replaced ```cmd with ```bash and removed $ for the setup commands to avoid wierd colors

[CLAassistant]

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[samugi]

markdown changes look ok, tagging @lena-larionova for a review by docs on the wording