Tasks: UI log snapshot display when paused

[mafredri]

Repo: coder/coder

Scope: Show stored log snapshot in task view when task is paused.

Design notes:

• Use task-centric terminology, avoid "workspace" language (TBD, see Figma)
• Header options: "Last N messages" (dynamic from API) or "Recent AI chat logs"
• All states must handle missing snapshot gracefully

Changes:

• Modify WorkspaceNotRunning component in TaskPage.tsx
• Fetch log snapshot from modified logs endpoint
• Display in plain text scrollable container (per PRD specification)
• Show message count (from API total_count) and snapshot timestamp
• If no snapshot: "No logs available (snapshot may have failed during pause, resume your task to view logs)."

Message formatting (implementation suggestion, verify with Figma/design):

• Each message separated by blank line
• Prefix with type indicator (e.g., [user] or [agent], following CLI's TYPE column)
• Preserve content whitespace/formatting
• Example:

  [user]
  What's the latest GH issue?
  
  [agent]
  I'll fetch that for you...
  The latest issue is #21309: Feature: Improve database migration...
  

Files:

• site/src/pages/TaskPage/TaskPage.tsx

Acceptance criteria:

• Log snapshot displayed when task is paused
• Scrollable text container for messages
• Timestamp shown indicating snapshot age
• Graceful handling when no snapshot exists
• Plain text rendering (not chat bubbles) per PRD
• Messages clearly distinguished by type prefix

Dependencies:

• Tasks: Return log snapshot from logs endpoint when paused #1254

References:

• PRD: Start/Pause/Resume the Task Workspace
• RFC: Tasks: Start/Pause/Resume Lifecycle: UI
• Figma: Tasks: Resume/stop/start