Add CSV Download Functionality to ResultSet Component

[Sano7707]

Summary

This PR adds the ability to download query results directly as a CSV file from the query results pane.

A new CSV action button has been added to the results toolbar alongside the existing actions. When clicked, the current result set is dynamically converted into a CSV file and downloaded locally. The generated file is automatically named using the corresponding queryId.

Implementation Details

The exported CSV is generated in the browser and follows standard CSV formatting rules, including proper escaping of:

• Double quotes
• Commas
• Newline characters

Null and undefined values are exported as empty fields.

UI Changes

A new CSV action button is added next to the existing actions in the results toolbar:

Example Behavior

Clicking the CSV button:

1. Formats the current query results as a CSV document.
2. Applies proper escaping for special characters.
3. Initiates a local file download.
4. Names the file using the associated queryId.

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