add file to chat in file tabs

[justschen]

fix https://github.com/microsoft/vscode-copilot/issues/18733

[vs-code-engineering]

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[bpasero]

This needs to respect tab-multi select, also are we considering this the final location of the action?

//cc @benibenj

[justschen]

ope, i'll give that a look, i know in explorer we can add multiple files.

we have it outside of a copilot submenu since it's the only thing in that menu, but we could consider matching where copilot is for other context menus.

[bpasero]

Yeah we are not very consistent, but most often have a "Copilot" submenu:

Except for search:

[benibenj]

Created an issue for the multi select scenario https://github.com/microsoft/vscode-copilot/issues/18823. It would be great if you would support this, thanks!