Horizontal scrollbar always rendered in extension chat panel even when content fits (VSCode extension)

Description

The Claude Code VSCode extension always shows a horizontal scrollbar at the bottom of the chat/sidebar panel, regardless of content. The scrollbar has nothing to scroll to — text wraps correctly within the visible width — so it appears to be a CSS layout bug rather than actual overflow.

Repro

1. Open the Claude Code VSCode extension on Windows
2. Observe the panel in any state: idle, during a response, in a permission prompt, etc.
3. The horizontal scrollbar is present at the bottom of the panel in every state.

(Screenshot can be attached manually — the scrollbar is visible during normal chat output as well as during permission prompts.)

Expected

No horizontal scrollbar when content fits the panel width via wrapping.

Comparison

The OpenAI Codex VSCode extension does not show a persistent horizontal scrollbar in its chat panel under the same VSCode version, so it isn't a webview platform limitation.

Environment

• VSCode on Windows 11 Enterprise (10.0.26100)
• Claude Code VSCode extension (current)

Suggested fix area

Likely a child element in the panel webview has a fixed min-width or white-space: pre that exceeds the panel's content box, forcing the parent to render a scrollbar. Candidates: overflow-x: hidden on the panel root, or min-width: 0 on flex/grid children that contain wrapped text.