Add support for file size limits on uploads

[grantcopley]

Objective:

Introduce a functionality in CBWIRE to specify and enforce a file upload size limit.

Details:

The enhancement involves the ability to set a maximum file size for uploads in CBWIRE. Currently, when a file upload is initiated, CBWIRE requests a signed upload URL and receives the file's size. This process presents an opportunity to implement size checks before the upload proceeds.

Initial Incoming Request:

{
  "fingerprint": {
    "id": "lqfNNk5kc2O5Gh8s9tAI",
    "name": "my-test",
    "locale": "en",
    "path": "/",
    "method": "GET",
    "v": "acj"
  },
  "serverMemo": {
    "children": [],
    "errors": [],
    "htmlHash": "48e6dd7c",
    "data": {
      "clicked": false,
      "myFile": ""
    },
    "dataMeta": [],
    "checksum": "8dd9b6e1456bd3c73651446497a4b72125ece6dd58c724815eb720c1e7f5e2d2"
  },
  "updates": [
    {
      "type": "callMethod",
      "payload": {
        "id": "ksfh",
        "method": "startUpload",
        "params": [
          "myFile",
          [
            {
              "name": "2022-08-21 07.52.50.gif",
              "size": 424008,
              "type": "image/gif"
            }
          ],
          false
        ]
      }
    }
  ]
}

Example Use Case:

An application requires users to upload profile pictures. To optimize storage and bandwidth, a size limit of 200KB is set for these images. When a user attempts to upload a file, CBWIRE checks the file size against this limit before proceeding with the upload.

Expected Functionality:

File Size Verification: On receiving the initial upload request, CBWIRE verifies the file size against a pre-set maximum limit.
Upload Approval/Denial: If the file size is within the allowed range, the upload proceeds. Otherwise, the upload is denied, and the user is notified of the size limitation.
Customizable Limits: Allow administrators or developers to set and modify the file size limits as per application requirements.