Feature: Export timeline view as image or shareable link

[thbst16]

Description

Users building public-facing timelines need ways to share specific views or export static images for presentations, social media, or embedding in articles.

Use Case

After building an NFL history timeline, I want to share a view focused on "Super Bowl I through X" as an image on social media, or generate a link that opens the timeline centered on a specific date with specific zoom level.

Proposed Solution

• Add onExport prop that provides export utilities
• Support formats: PNG, SVG, and shareable URL with state encoded
• Provide getShareableUrl() method that encodes current view state (center date, zoom, filters)
• Add optional export button via showExportButton prop

Example API

const timelineRef = useRef();

<Timeline
  ref={timelineRef}
  data={data}
  showExportButton={true}
/>

// Programmatic access
timelineRef.current.exportAsImage('png');
timelineRef.current.getShareableUrl(); // Returns URL with encoded state

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Issue generated from user feedback while building an NFL history timeline