UI Consistency: Standardize grids, colors, and spacing

[samkeen]

Summary

Standardize UI elements across pages for visual consistency.

Tasks

• Standardize summary card grid columns (currently 3-col vs 4-col on different pages)
• Create unified color palette for message types in session-tabs:
  • User messages: bg-blue-50 dark:bg-blue-950
  • Assistant messages: bg-zinc-50 dark:bg-zinc-900
  • Tool use: bg-zinc-100 dark:bg-zinc-800
  • Thinking: bg-purple-50 dark:bg-purple-950
  • Tool result: bg-green-50 dark:bg-green-950
• Standardize max-height values (currently using 48, 64, 96 inconsistently)
• Standardize text colors (text-zinc-600 dark:text-zinc-400 pattern)
• Standardize border colors across components

Files to update

• components/session-tabs.tsx
• app/projects/[id]/page.tsx
• app/projects/[id]/sessions/[sessionId]/page.tsx