docs: add robots.txt for SEO engines

[Guts]

No description provided.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.78%. Comparing base (8189be1) to head (3c2220a).
Report is 5 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #458   +/-   ##
=======================================
  Coverage   71.78%   71.78%           
=======================================
  Files          45       45           
  Lines        2715     2715           
  Branches      587      587           
=======================================
  Hits         1949     1949           
  Misses        582      582           
  Partials      184      184           

Flag	Coverage Δ
unittests	71.27% <ø> (ø)

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