[Toolset] Language dropdown in Add locale dialog is too narrow and truncates its value

[dariacherepanova]

DIAL chat version

0.0.1

How to reproduce

1. Open the Toolset Editor.
2. Click Add locale.
3. Observe the Language dropdown.
4. Open the dropdown or check the currently displayed value/placeholder.

Actual result

The Language dropdown is significantly narrower than the adjacent Name field.

Because of the limited width:

• the selected value or placeholder is truncated, e.g. displayed as S...;
• locale codes or language names may not be fully readable;
• the control looks visually inconsistent with the rest of the form.

Expected result

The Language dropdown should have sufficient width to display supported locale values without unnecessary truncation.

The control should either:

• use a wider fixed/minimum width; or
• expand responsively according to its content/layout.

Common locale values such as en-US, de-DE, pt-BR, etc. should be fully visible.

Confidential information

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[PolinaGurinovich97]

One thing to expect when retesting: the "Add locales" button is hidden for now, so the widened dropdown is not reachable. The list of content locales is a hardcoded, currently empty array, so the popup could never be satisfied (see #8786) and the control is not rendered at all. Making that list runtime-configurable is tracked in #8803 — the width fix is in place and will show once a locale is configured.