feat(esmole): mapping flatten

packages/esmole-mcp/test/unit/es/mapping.test.ts

@@ -0,0 +1,40 @@
+import { describe, expect, it } from 'vitest'
+import { flattenMapping } from '../../../src/es/mapping.js'
+
+const raw = {
+    myindex: {
+        mappings: {
+            properties: {
+                id: { type: 'keyword' },
+                title: { type: 'text', fields: { raw: { type: 'keyword' } } },
+                author: { properties: { name: { type: 'text' }, age: { type: 'integer' } } }
+            }
+        }
+    }
+}
+
+describe('flattenMapping', () => {
+    it('flattens nested properties to dotted field:type rows', () => {
+        const rows = flattenMapping(raw)
+        expect(rows).toContainEqual({ field: 'id', type: 'keyword' })
+        expect(rows).toContainEqual({ field: 'title', type: 'text' })
+        expect(rows).toContainEqual({ field: 'title.raw', type: 'keyword' })
+        expect(rows).toContainEqual({ field: 'author.name', type: 'text' })
+        expect(rows).toContainEqual({ field: 'author.age', type: 'integer' })
+    })
+    it('handles multiple indices by prefixing the index name', () => {
+        const rows = flattenMapping({
+            a: { mappings: { properties: { x: { type: 'long' } } } },
+            b: { mappings: { properties: { y: { type: 'date' } } } }
+        })
+        expect(rows).toContainEqual({ index: 'a', field: 'x', type: 'long' })
+        expect(rows).toContainEqual({ index: 'b', field: 'y', type: 'date' })
+    })
+    it('returns empty array for an empty mapping', () => {
+        expect(flattenMapping({ idx: { mappings: {} } })).toEqual([])
+    })
+    it('returns empty array for a non-object input', () => {
+        expect(flattenMapping(null)).toEqual([])
+        expect(flattenMapping('nope')).toEqual([])
+    })
+})