Two small visual refinements to the assistant message body, found
during a careful visual comparison against established chat UI
conventions:

1. Add `padding: 0 12px 0 4px` to .chat-message__assistant-body —
   the previous zero horizontal padding let text touch container
   edges (especially noticeable in narrow containers like popup +
   sidebar). 12px right gives breathing room before the right edge;
   4px left keeps a slight inset so the text doesn't crash into any
   left-side adornment.

2. Tighten the assistant body line-height from 1.6 to 1.55. The
   1.6 felt slightly airy; 1.55 reads more compactly while still
   well above WCAG minimum. Markdown paragraphs keep their own
   line-height (1.75) per chat-markdown.styles, so this only
   affects plain assistant text.

Pure CSS, no API change. Bumps @ngaf/chat to 0.0.7.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>