Update CLAUDE.md with deep link sharing documentation

- Document new deep link sharing functionality
- Explain all supported URL parameters
- Add example deep links
- Note reasoning panel state preservation
- Update reasoning trace section with URL state info

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

CLAUDE.md

@@ -8,6 +8,34 @@ OCR Text Explorer is a modern, standalone web application for browsing and compa
 
 ## Recent Updates
 
+### Deep Link Sharing (Added 2025-08-07)
+
+The application now supports deep linking with full state preservation for easy sharing and collaboration:
+
+**Features:**
+- Complete URL state management for all view settings
+- Copy Link button for one-click sharing
+- Automatic restoration of view state from URL parameters
+- Success notification when link is copied
+
+**URL Parameters Supported:**
+- `dataset` - HuggingFace dataset ID
+- `index` - Sample index (0-based)
+- `view` - View mode (comparison, diff, improved)
+- `diff` - Diff algorithm (char, word, line, markdown)
+- `markdown` - Markdown rendering state (true/false)
+- `reasoning` - Reasoning panel expansion state (true/false, only for samples with reasoning traces)
+
+**Implementation Details:**
+- URL updates automatically as users navigate and change settings
+- Prevents double-loading when URL contains specific index
+- Fallback clipboard API support for older browsers
+- Reasoning state only included in URL when reasoning trace is present
+
+**Example Deep Links:**
+- Basic: `/?dataset=davanstrien/exams-ocr&index=5`
+- Full state: `/?dataset=davanstrien/india-medical-ocr-test&index=0&view=improved&diff=word&markdown=true&reasoning=true`
+
 ### Reasoning Trace Support (Added 2025-08-07)
 
 The application now supports displaying reasoning traces from models like NuMarkdown-8B-Thinking that include their analysis process in the output:
@@ -19,6 +47,7 @@ The application now supports displaying reasoning traces from models like NuMark
 - Reasoning statistics (word count, percentage of total output)
 - Support for formatted reasoning steps with numbered analysis points
 - "Reasoning Trace" badge indicator in the statistics panel
+- Deep link support preserves reasoning panel state
 
 **Implementation Details:**
 - New `reasoning-parser.js` module handles detection and parsing of reasoning traces
@@ -26,6 +55,7 @@ The application now supports displaying reasoning traces from models like NuMark
 - Formats numbered steps from reasoning content for structured display
 - Caches parsed reasoning to avoid reprocessing
 - Exports include optional reasoning trace content
+- Reasoning panel state included in shareable URLs
 
 **Supported Datasets:**
 - `davanstrien/india-medical-ocr-test` - Medical documents processed with NuMarkdown-8B-Thinking