feat: add snowflake-development for Snowflake SQL, pipelines, Cortex AI, and Snowpark (#395)
* feat: add snowflake-development for Snowflake SQL, pipelines, Cortex AI, and Snowpark
Comprehensive Snowflake development skill covering SQL best practices, data pipeline
design (Dynamic Tables, Streams, Tasks, Snowpipe), Cortex AI functions, Cortex Agents,
Snowpark Python, dbt integration, performance tuning, and security hardening.
* fix: separate dbt materialization configs into distinct examples