[TUI] Feature — Dedicated Issue/Item Detail View

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Overview

Viewing an individual issue's full details (rendered markdown body, comments, labels, assignees, linked PRs, timeline) needs a dedicated view. In gh-dash, the preview pane shows a truncated view and you often have to press o to open the browser, defeating the purpose of a terminal tool.

Current State

No full-detail view for individual items. Users must open the browser to read complete issue content.

Proposed Solution

Pressing enter on any item opens a dedicated detail screen showing:

• Title and state (open/closed)
• Full body with markdown rendering (using glamour or similar)
• Labels, assignees, milestone
• Comments thread (scrollable)
• Linked PRs or related items
• Metadata (created date, last updated, author)
• Local notes (from offline notes feature) displayed separately

Navigation within the detail view:

• j/k to scroll
• c to jump to comments section
• n to add/edit a local note
• o to open in browser
• q or Esc to go back
• Fullscreen/zen mode toggle should work here too

This view should also be cacheable — once opened, its full detail is stored locally and available offline.

Priority

High. Core TUI functionality.

Acceptance Criteria

• enter on any item opens a full-detail screen
• Issue body is rendered with markdown formatting
• Labels, assignees, milestone, and metadata are displayed
• Comments thread is scrollable
• j/k scrolls, q/Esc goes back, o opens in browser
• Detail view is cached for offline access