Thanks for the feedback.

What you are asking for, in the context of autodiscovery, is a topic that puzzled me for a while, but I couldn't find a way to easily handle it due to the number of edge cases. And to me, the effort wasn't worth it.
So the short answer is no, but...

To the question can we have a branch name like updatecli/helm-prometheus-node-exporter-4.47.3, the answer is just no because contrary to Renovabot, Updatecli is a command line tool that doesn't use any state, excepted maybe the information stored in the pull/merge request body. That you run it from your CI or your machine, the end result must remain the same.
For example, if Updatecli run a first time against the version "4.47.2" and a second time against the version "4.47.3", it would need a way to identify that the MR updatecli/helm-prometheus-node-exporter-4.47.2 is an obsolete version of the MR updatecli/helm-prometheus-node-exporter-4.47.3 and therefor need to be closed. To simplify the maintenance of Updatecli, I made the decision to reuse the same branch name and to git reset its content when needed.

The question can we have commit like fix: update helm prometheus-node-exporter ( 4.47.2 → 4.47.3 ), yes we could
We would need to update autodiscovery manifest template such as helmreleaseManifestTemplate, but we would also have edge cases to deal with for example once #6032 is merged, having detailed commit message could be hard to maintain over time with squashed commits

In the context of declarative pipeline, you can use the parameter pipelineid to control the name of the temporary branch
as explained on https://www.updatecli.io/docs/core/configuration

And you can change the branch prefix updatecli by whatever you want using workingbranchprefix and to replace the branch separator _ by something like /
Here is an example

  pipelineid: helm-prometheus-node-exporter
  scms:
    default:
      kind: github
      spec:
        branch: "{{ .scm.branch }}"
        email: "{{ .scm.email }}"
        owner: "{{ .scm.owner }}"
        repository: "{{ .scm.repository }}"
        token: '{{ requiredEnv "GITHUB_TOKEN" }}'
        user: "{{ .scm.user }}"
        username: '{{ requiredEnv "GITHUB_ACTOR" }}'
        workingbranchprefix: "deps"
        workingbranchseparator: '/' 
      disabled: false

Looking at https://www.updatecli.io/docs/plugins/scm/gitlab/, I realize that the table parameter update is broken, normally workingbranchprefix and workingbranchseparator should be mentioned. I'll fix that