Universal data agent skill for natural language database querying, schema visualization, and automated chart generation. Use when working with databases, analyzing data, creating visualizations, exploring table structures, or needing insights from PostgreSQL, MySQL, SQLite, BigQuery, Snowflake, or Redshift. Triggers include "query the database", "analyze this data", "show me a chart", "visualize the schema", "what's in this table", or any data exploration tasks.