docs: Change buttons + remove duplicate redirection

[thomaspoignant]

Description

• Change the top buttons on the home page
• Remove duplicate redirection

Checklist

• I have updated the documentation (README.md and /website/docs)
• I have followed the contributing guide

[netlify]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.79%. Comparing base (93672b0) to head (7a39676).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2887   +/-   ##
=======================================
  Coverage   84.79%   84.79%           
=======================================
  Files         111      111           
  Lines        5195     5195           
=======================================
  Hits         4405     4405           
  Misses        625      625           
  Partials      165      165           

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[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud