Add option to export query results to CSV in dark theme for Query Manager #17519

Description

When exporting query results from the Query Manager to CSV in dark mode, the file is exported with light-theme colors baked into the styling, making rows harder to read.

Expected Behavior

Exported CSV should be plain text (no embedded colors/styles), consistent regardless of active theme.

Steps to Reproduce

1. Switch ToolJet UI to dark mode
2. Run a query in the Query Manager
3. Export results to CSV
4. Open the CSV and observe embedded theme colors

Environment

• ToolJet version: latest
• OS: Linux