debug: Add symbol type logging to analyze_symbol

This will show us exactly what symbol is being passed to the analysis function
when you test it on Hugging Face. We can see if there's a data type or value issue.

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

Co-Authored-By: Claude <noreply@anthropic.com>

app.py

@@ -757,6 +757,7 @@ def analyze_symbol(symbol: str):
     """Analyze a single symbol using TimesFM"""
     try:
         print(f"🔍 Starting TimesFM analysis for {symbol}")
+        print(f"📊 Symbol type: {type(symbol)}, value: '{symbol}'")
 
         data = get_cached_data(symbol)