feat(csv-loader): preserve original schema strings in type generation

Store the original schema string during CSV parsing to prevent
unnecessary expansion of type name references in the generated
TypeScript definitions. This ensures that declared types reference
each other by name rather than inlining their full definitions.

src/csv-loader/loader.ts

@@ -160,7 +160,11 @@ export function parseCsv(
   }
 
   // Parse type declarations with expansion of type name references
-  const typeDeclarationsParsed: { name: string; schema: Schema }[] = [];
+  const typeDeclarationsParsed: {
+    name: string;
+    schema: Schema;
+    schemaString: string;
+  }[] = [];
   for (const decl of typeDeclarationsRaw) {
     // Expand any type name references before parsing
     const expandedSchema = expandSchemaString(
@@ -168,7 +172,11 @@ export function parseCsv(
       declaredSchemaStrings,
     );
     const schema = parseSchema(expandedSchema.trim());
-    typeDeclarationsParsed.push({ name: decl.typeName, schema });
+    typeDeclarationsParsed.push({
+      name: decl.typeName,
+      schema,
+      schemaString: decl.schemaString,
+    });
   }
 
   // Build declared types map
@@ -181,7 +189,11 @@ export function parseCsv(
   const typeDeclarations: TypeDeclaration[] = [];
   for (const decl of typeDeclarationsParsed) {
     const resolvedSchema = resolveTypeReferences(decl.schema, declaredTypes);
-    typeDeclarations.push({ name: decl.name, schema: resolvedSchema });
+    typeDeclarations.push({
+      name: decl.name,
+      schema: resolvedSchema,
+      schemaString: decl.schemaString,
+    });
   }
 
   // Update declaredTypes with resolved schemas for column schema lookup