Add psalm static analysis

[caendesilva]

https://shepherd.dev/github/hydephp/develop

[codecov]

Codecov Report

Merging #301 (5f4f06d) into master (3d6eb64) will not change coverage.
The diff coverage is n/a.

❗ Current head 5f4f06d differs from pull request most recent head 80dc9c2. Consider uploading reports for the commit 80dc9c2 to get more accurate results

@@             Coverage Diff             @@
##              master      #301   +/-   ##
===========================================
  Coverage     100.00%   100.00%           
  Complexity       831       831           
===========================================
  Files             99        99           
  Lines           2078      2078           
===========================================
  Hits            2078      2078           

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