Add QuickTranslator plugin

[thorthello]

Plugin Summary

• Name: QuickTranslator
• Description: QuickTranslator is a lightweight translation extension for ONLYOFFICE. It allows users to translate selected text or custom input directly within a dedicated left side panel and offers one-click insertion back into the document. It automatically detects selected text and remembers the user's preferred target language.
• License: GNU General Public License v3.0 (GPL-3.0)

Features

• Instant translation within the left side panel.
• Automatic translation upon text selection.
• Remembers preferred target language using localStorage.
• Supports Dark Mode theme.
• Easy "Insert" button to replace selection with translated text.

Verification

• Tested in ONLYOFFICE Docs (Web)
• Tested with Light and Dark themes
• Tested selected text auto-translation

[CLAassistant]

All committers have signed the CLA.

[drape3a]

Hi @thorthello

Thank you for your contribution!
A few things missing for the marketplace:

1. offered in config.json — vendor name string:

"offered": "Your Name or Organization"

2. store block in variations — screenshots, store icons, categories, background. Files under resources/store/. See onlymath or insertQR for the exact shape.

3. translations/langs.json — this is what drives the languages shown on your plugin's marketplace page, so without it the listing has no language info. Every plugin in the repo ships one. It lists the additional locales you provide; English is the base from the markup, so [] is valid if the plugin is English-only: []

4. CHANGELOG.md — displayed on the plugin page in the marketplace, so users can see what changed between versions.

5. Dark theme support — currently the plugin is light-only.