feat: complete code cleanup and create feature parity plan

Major Architecture Improvements:
- Separate JavaScript library (lib/) with proper build system
- Go CLI with embedded library using go:embed
- Hot reload development with Air integration
- Library + CLI build pipeline with npm run build

Code Cleanup:
- Remove obsolete assets (insertr-cli/assets/editor/)
- Clean up package.json metadata and dependencies
- Update .gitignore for new architecture
- Remove unused 'marked' dependency

New Documentation:
- Add comprehensive TODO.md with feature gap analysis
- Document critical gaps between prototype and current library
- Create phased implementation plan for feature parity
- Update DEVELOPMENT.md with hot reload workflow
- Add LIBRARY.md documenting new architecture

Hot Reload System:
- Air watches both Go CLI and JavaScript library
- Library changes trigger: rebuild → copy → CLI rebuild → serve
- Seamless development experience across full stack

Next Steps:
- Current library is basic proof-of-concept (prompt() editing)
- Archived prototype has production-ready features
- Phase 1 focuses on professional forms and authentication
- Phase 2 adds validation and content persistence

test-hot-reload.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+
+# Test script to demonstrate Air hot reload functionality
+# Shows how library changes automatically trigger CLI rebuild
+
+echo "🧪 Testing Insertr Hot Reload Functionality"
+echo "============================================"
+
+cd insertr-cli
+
+echo "1. Starting Air in background..."
+air &
+AIR_PID=$!
+sleep 5
+
+echo "2. Making a test change to the library..."
+cd ../lib/src
+# Make a test change
+sed -i 's/Hot Reload Ready/Hot Reload TESTED/g' index.js
+
+echo "3. Waiting for Air to detect change and rebuild..."
+sleep 8
+
+echo "4. Testing if the change was embedded in CLI..."
+cd ../insertr-cli
+if ./insertr enhance ../demo-site/ -o /tmp/test-output 2>/dev/null && grep -q "Hot Reload TESTED" /tmp/test-output/index.html; then
+    echo "✅ SUCCESS: Library change was automatically embedded in CLI!"
+else
+    echo "❌ FAILED: Library change was not embedded"
+fi
+
+echo "5. Reverting test change..."
+cd ../lib/src
+sed -i 's/Hot Reload TESTED/Hot Reload Ready/g' index.js
+
+echo "6. Stopping Air..."
+kill $AIR_PID 2>/dev/null
+wait $AIR_PID 2>/dev/null
+
+echo ""
+echo "🎉 Hot reload test completed!"
+echo "   Library changes automatically trigger:"
+echo "   • Library rebuild (npm run build)"
+echo "   • Asset copy to CLI"
+echo "   • CLI rebuild with embedded library"
+echo "   • Development server restart"