Module evolution 

Schema evolution engine (F-SCHEMA-009).

Provides:

• DefaultSchemaEvolver — a general-purpose implementation of SchemaEvolvable that performs name-based schema diffing, compatibility evaluation, and schema merging
• SchemaEvolutionEngine — orchestrates the full evolution flow: detect → diff → evaluate → apply → record
• SchemaHistory — tracks per-source schema version history
• is_safe_widening — determines whether a type can be safely widened

Structs

DefaultSchemaEvolver

A general-purpose implementation of SchemaEvolvable that uses name-based schema matching (suitable for JSON, CSV, Avro, etc.).

SchemaEvolutionEngine

Orchestrates the full schema evolution flow.

SchemaHistory

Tracks schema version history for all sources.

SchemaHistoryEntry

A record in the schema history.

Enums

EvolutionResult

Result of an evolution attempt.

EvolutionTrigger

How a schema evolution was triggered.

Functions

apply_changes

Applies a set of schema changes to produce a new schema and a column projection mapping old columns to new positions.

diff_schemas_by_name

Computes the diff between two Arrow schemas using name-based matching.

evaluate_changes

Evaluates a set of schema changes against a compatibility mode.

is_safe_widening

Returns true if from can be safely widened to to without data loss.