feat: blobs fetch

Signed-off-by: Sebastian Krupinski <krupinski01@gmail.com>

src/services/entityService.ts

@@ -28,6 +28,9 @@ import type {
   EntityPatchResponse,
   EntityPatchRequest,
   EntityDownloadRequest,
+  EntityBlobsRequest,
+  EntityBlobsResponse,
+  EntityBlobsWireResponse,
 } from '../types/entity';
 import { useIntegrationStore } from '@KTXC/stores/integrationStore';
 import { EntityObject } from '../models';
@@ -227,6 +230,36 @@ export const entityService = {
   download(request: EntityDownloadRequest): { transaction: string } {
     return transceiveDownload<EntityDownloadRequest>('entity.download', request);
   },
+
+  /**
+   * Fetch one or more message parts (attachments) inline for rendering.
+   *
+   * Returns JSON with base64-encoded bytes; each result is decoded into a Blob
+   * so callers can create object URLs for preview.
+   */
+  async blobs(request: EntityBlobsRequest): Promise<EntityBlobsResponse> {
+    const wire = await transceivePost<EntityBlobsRequest, EntityBlobsWireResponse>(
+      'entity.blobs',
+      request,
+    );
+    return wire.map((result) => ({
+      source: result.source,
+      part: result.part,
+      mime: result.mime,
+      filename: result.filename,
+      blob: base64ToBlob(result.bytes, result.mime),
+    }));
+  },
 };
 
+/** Decode base64 content into a Blob of the given MIME type. */
+function base64ToBlob(base64: string, mime: string): Blob {
+  const binary = atob(base64);
+  const bytes = new Uint8Array(binary.length);
+  for (let i = 0; i < binary.length; i++) {
+    bytes[i] = binary.charCodeAt(i);
+  }
+  return new Blob([bytes], { type: mime });
+}
+
 export default entityService;