feat: complete candle annotator implementation

- Created CandleChart component with lightweight-charts integration
- Implemented SvgOverlay component for line drawing
- Integrated all components in main page
- Fixed TypeScript and Tailwind CSS compatibility issues
- Added comprehensive README.md with project documentation
- Created DEPLOYMENT.md with setup and troubleshooting guide
- Downgraded to stable versions (Tailwind v3, lightweight-charts v4)
- All 59 tasks from OpenSpec completed

src/app/page.tsx

@@ -1,19 +1,26 @@
 'use client';
 
-import { useState } from 'react';
+import { useState, useRef } from 'react';
 import Toolbox, { Tool } from '@/components/Toolbox';
 import FileUpload from '@/components/FileUpload';
+import CandleChart, { CandleChartHandle } from '@/components/CandleChart';
 
 export default function Home() {
   const [activeTool, setActiveTool] = useState<Tool>(null);
+  const chartRef = useRef<CandleChartHandle>(null);
 
   const handleExport = () => {
     window.location.href = '/api/export';
   };
 
   const handleUploadSuccess = () => {
-    // TODO: Trigger chart refresh
-    console.log('Upload successful - refresh chart');
+    // Refresh chart data after successful upload
+    chartRef.current?.refreshData();
+  };
+
+  const handleAnnotationChange = () => {
+    // Refresh chart when annotations change
+    chartRef.current?.refreshData();
   };
 
   return (
@@ -34,11 +41,12 @@ export default function Home() {
       </aside>
 
       {/* Main chart area */}
-      <main className="flex-1 flex items-center justify-center bg-background">
-        <div className="text-muted-foreground text-center">
-          <p className="text-lg">Upload a CSV file to view the candlestick chart</p>
-          <p className="text-sm mt-2">CSV format: time, open, high, low, close</p>
-        </div>
+      <main className="flex-1 relative">
+        <CandleChart
+          ref={chartRef}
+          activeTool={activeTool}
+          onAnnotationChange={handleAnnotationChange}
+        />
       </main>
     </div>
   );