Create Bulk Transactions Upload URL

Generates up to 10 presigned PUT URLs for uploading JSONL transaction files (up to 5GB each) directly to storage. Each URL is valid for 15 minutes. Use the returned URL to upload the file via an HTTP PUT request with the binary file content as the body. If a URL expires before the upload completes, you must request a new one. Files can be uploaded as plain JSONL or as a gzip-compressed file. Supports both incomingTransactionsFile for daily transaction ingestion and historicalTransactionsFile for historical transaction ingestion. See the Historical Transaction Uploads integration guide for details on the historical flow. <b>Required scopes:</b> files:write