feat: add comprehensive error tracking with full tracebacks

- Capture exception type and full traceback for better debugging
- Include traceback in debug files for failed forecasts
- Bump version to v1.0.4 for deployment tracking
- This will help diagnose the mysterious empty error messages

src/forecasting/chronos_inference.py

@@ -2,7 +2,7 @@
 """
 Chronos-2 Inference Pipeline
 Standalone inference script for HuggingFace Space deployment.
-FORCE REBUILD: v1.0.3
+FORCE REBUILD: v1.0.4
 """
 
 import os
@@ -172,7 +172,7 @@ class ChronosInferencePipeline:
 
                 # Get target column name (note: dynamic_forecast renames it to 'target')
                 target_col = 'target'
-                print(f"[DEBUG v1.0.3] Using target_col='{target_col}', columns available: {list(context_data.columns)}", flush=True)
+                print(f"[DEBUG v1.0.4] Using target_col='{target_col}', columns available: {list(context_data.columns)}", flush=True)
 
                 # Extract context values
                 context = context_data[target_col].values
@@ -198,8 +198,12 @@ class ChronosInferencePipeline:
                 print(f"  ✓ Complete in {time.time() - border_start:.1f}s")
 
             except Exception as e:
-                print(f"  ✗ Error: {str(e)}")
-                results['borders'][border] = {'error': str(e)}
+                import traceback
+                error_msg = f"{type(e).__name__}: {str(e)}"
+                traceback_str = traceback.format_exc()
+                print(f"  ✗ Error: {error_msg}", flush=True)
+                print(f"Traceback:\n{traceback_str}", flush=True)
+                results['borders'][border] = {'error': error_msg, 'traceback': traceback_str}
 
         # Add summary metadata
         results['metadata']['total_time_s'] = time.time() - total_start
@@ -317,6 +321,8 @@ def run_inference(
         for border, data in results['borders'].items():
             if 'error' in data:
                 f.write(f"  {border}: ERROR - {data['error']}\n")
+                if 'traceback' in data:
+                    f.write(f"\nFull Traceback:\n{data['traceback']}\n")
             else:
                 f.write(f"  {border}: OK\n")
                 f.write(f"    median count: {len(data.get('median', []))}\n")