Y25-715 - creating a balanced pool tube as soon as the first run finishes

[KatyTaylor]

Closes #2654

See related Integration Suite change - https://gitlab.internal.sanger.ac.uk/psd/integration-suite/-/merge_requests/305 - the test was not broken, but this removes now-unnecessary parts.

Changes proposed in this pull request

• remove plate_downstream_completed_presenter and related code due to change in requirement

Instructions for Reviewers

[All PRs] - Confirm PR template filled
[Feature Branches] - Review code
[Production Merges to main]
    - Check story numbers included
    - Check for debug code
    - Check version

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.61%. Comparing base (1b9b14c) to head (71b1558).
⚠️ Report is 24 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #2707      +/-   ##
===========================================
+ Coverage    84.59%   84.61%   +0.02%     
===========================================
  Files          501      500       -1     
  Lines        20538    20578      +40     
  Branches       377      377              
===========================================
+ Hits         17374    17412      +38     
- Misses        3161     3163       +2     
  Partials         3        3              

Flag	Coverage Δ
javascript	79.71% <ø> (ø)
pull_request	84.57% <ø> (-0.02%)	⬇️
push	84.54% <ø> (-0.06%)	⬇️
ruby	92.57% <ø> (+0.01%)	⬆️

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[KatyTaylor]

Screenshots of button showing / not showing in different states:

No children made yet, charge and pass not pressed yet:

No children yet, charge and pass clicked:

EqVol child made, sequencing requests not passed yet:

End of the pipeline, EqVol and EqMol tubes all made: