Add Agent, Source, and MappingSpecification classes to schema

Introduces new classes (Agent, Source, MappingSpecification) and associated slots to the fair_mappings_schema.yaml.

Author: matentzn

src/fair_mappings_schema/schema/fair_mappings_schema.yaml

@@ -21,3 +21,89 @@ default_range: string
 imports:
   - linkml:types
 
+classes:
+
+  Agent:
+    description: An entity that can create or contribute to a digital object, such as an author or creator.
+    slots:
+      - id
+      - name
+  
+  Source:
+    description: >-
+      A data source from which entities are drawn, such as a database, ontology, or vocabulary.
+    slots:
+      - name
+      - version
+      - type
+      - documentation
+      - content
+      - content_type
+  MappingSpecification:
+    description: >-
+      A formal description of correspondences between entities in a source and a target, expressed as rules, functions, or mapping statements.
+    slots:
+      - author
+      - creator
+      - publication_date
+      - license
+      - version
+      - description
+      - type
+      - mapping_method
+      - documentation
+      - content
+      - subject_source
+      - object_source
+
+slots:
+  id:
+    description: Identifier for the information entity
+    identifier: true
+    range: string
+  name:
+    description: Name of the information entity
+    range: string
+  creator:
+    description: Creator of the mapping specification
+    range: Agent
+    inlined: true
+  author:
+    description: Author of the mapping specification
+    range: Agent
+    inlined: true
+  publication_date:
+    description: Date of publication of the mapping specification
+    range: string
+  license:
+    description: License under which the mapping specification is released
+    range: string
+  version:
+    description: Version of the digital object
+    range: string
+  description:
+    description: A brief description of the mapping specification
+    range: string
+  type:
+    description: Type of the information entity
+    range: string
+  mapping_method:
+    description: Method used to create the mapping specification
+    range: string
+  documentation:
+    description: URL or reference to documentation for the mapping specification
+    range: string
+  content:
+    description: Reference to the actual content of the digital object
+    range: string
+  content_type:
+    description: The type of the content of the digital object
+    range: string
+  subject_source:
+    description: The source from which the subject entities are drawn
+    range: Source
+    inlined: true
+  object_source:
+    description: The source from which the object entities are drawn
+    range: Source
+    inlined: true