feat: Add Chinese translation

[Szkkhh]

Description

Type of change

Please delete options that are not relevant.

• New language

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules

[Copilot]

Pull request overview

This pull request adds a Chinese language translation file to support Chinese users of the CounterForMessenger application. The translation follows the established pattern used by other language files in the repository.

Changes:

• Added Chinese.py with 59 translation strings covering all UI elements of the application

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[Kubis10]

HI! Thanks a lot for the PR