feat: Update Czech translations

[jantomicky]

Improves Czech admin translations by fixing typos & adding more translations.

[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
0 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 SonarCloud

[kingjia90]

Thank you for your PR!
I am sorry to inform that i have to close this.

Due to our import/export workflow, we can only accept translation via POEditor, only new keys (english only) need to be added via a PR.