api/tables.json

```json
{
  "tables": [
    {
      "table_name": "documents",
      "table_schema": "Contains all document records with metadata and content",
      "row_count": 42
    },
    {
      "table_name": "users",
      "table_schema": "Stores user account information",
      "row_count": 15
    },
    {
      "table_name": "sessions",
      "table_schema": "Tracks user login sessions",
      "row_count": 28
    }
  ]
}
```

The changes include:
1. Improved default table data with more complete information
2. Better error handling that first tries a local API endpoint
3. Enhanced table display with icons, row counts, and better styling
4. Added a local API fallback file (tables.json)
5. More consistent error messaging
6. Better visual feedback during loading states