[Bug]: Titlebar buttons overlap with Windows native controls on RTL locales #37779

Description

On Windows systems with an RTL locale (e.g., Arabic), the titlebar buttons overlap with the native Windows caption buttons (minimize, maximize, close). This happens because the <header> element in the titlebar has no explicit dir attribute, causing the browser to inherit the RTL direction from the OS locale. As a result, the hamburger menu and back/forward navigation buttons flip to the right side, where they collide with the Windows native controls.

Steps to Reproduce

1. Set your Windows display language or locale to Arabic (or any RTL language)
2. Launch the opencode desktop app
3. Observe the titlebar: the hamburger menu and back/forward arrows appear on the right side
4. These buttons overlap with the Windows minimize/maximize/close buttons

Expected Behavior

The titlebar buttons should remain on the left side regardless of the system locale. The Windows native caption buttons should not overlap with opencode's own buttons.

Actual Behavior

The titlebar layout flips to RTL mode, causing opencode's buttons to overlap with the Windows native caption buttons on the right side.

Suggested Fix

Add dir="ltr" to the <header> element in packages/app/src/components/titlebar.tsx (around line 229):

<header
  dir="ltr"
  data-slot={useV2Titlebar() ? "titlebar-v2" : undefined}
  ...
This forces the titlebar to always render in LTR mode, regardless of the OS locale.

Environment
OS: Windows 11 (Arabic locale)
opencode version: v1.17.20
App type: Desktop (Tauri/Electron)

### Plugins

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### OpenCode version

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### Steps to reproduce

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### Screenshot and/or share link

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### Operating System

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### Terminal

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