[osipovartem]

Parse Snowflake literal schema properties without rewriting SQL:

CREATE SCHEMA app COMMENT = 'application schema' DATA_RETENTION_TIME_IN_DAYS = 0;

• Preserve ordered assignments, duplicates and literals for the execution consumer to validate.
• Enable the syntax through a dialect capability; other dialects retain their existing valid forms.
• Reject unrepresented CREATE modifiers rather than silently erasing them.
• Add round-trip, malformed input, statement-boundary, serde and visitor controls.

Validation: 1,599 tests passed, seven ignored; all-target/all-feature strict Clippy and formatting passed. Independent read-only review approved the source. Coordinated DataFusion/Rustice builds and owning/Bronze tests passed with this exact parser revision.

The additive CreateSchema.schema_options field requires Rust consumers with exhaustive constructors/patterns to update. Serde defaults preserve older serialized input. Parsing does not imply runtime support.

Reference: https://docs.snowflake.com/en/sql-reference/sql/create-schema