Pass input JSON value parameter as-is to the API call

[zliang-akamai]

📝 Description

Previously the value of a JSON parameter passed in by the user had to go through _traverse_request_body function to have null or empty list/dict values remove. We did have a way to allow explicit empty dict/list but that won't work if the empty dict/list is nested in the JSON object.

Here is an example:

linode-cli linodes create \
  --image 'linode/ubuntu24.04' \
  --interface_generation linode \
  --interfaces '[{"firewall_id":123456,"public":{}}]' \
  --private_ip false \
  --region us-mia \
  --type g6-nanode-1 \
  --label test-cli-create-linode-public \
  --root_pass 'this-is-an-unsafe-password' \
  --disk_encryption enabled --debug

The JSON value parameter interfaces with user input JSON string '[{"firewall_id":123456,"public":{}}]' would be translated into an invalid API call request body attribute, which had {} removed:

{
    "interfaces": [{"firewall_id": 2431805}]
}

(irrelevant attributes in the body are ignored)

This change will let the CLI to pass whatever user input as-is into the request body to resolve this issue.

This is a potential breaking change because if user passed in some JSON like {"a": {}, b: {"key": "value"}} and expected key a would be dropped, this change will break their code. But I believe this change is necessary to make CLI behaviors correct and there isn't another easy way to fix the bug.

I think ExplicitEmptyDictValue can be safely removed because the empty dict will also be wrapped in ExplicitJsonValue.

✔️ How to Test

make install && linode-cli linodes create \
  --image 'linode/ubuntu24.04' \
  --interface_generation linode \
  --interfaces '[{"firewall_id":1629606,"public":{}}]' \
  --private_ip false \
  --region us-ord \
  --type g6-nanode-1 \
  --label test-cli-create-linode-public \
  --root_pass 'this-is-an-unsafe-password' \
  --disk_encryption enabled --debug

[lgarber-akamai]

Looks great! As privately discussed, this is technically a breaking change but it likely doesn't have a large impact and better aligns with the expectations our documentation sets for users.

[ezilber-akamai]

Nice work!