Allow realizing multiple cached branches at once

[FliegendeWurst]

Intended Change

This PR changes the "Copy referenced proof steps here" action to allow applying it on any node that has leaf children with caching info. It will then copy the referenced proof steps for all cached branches.

Type of pull request

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] Refactoring (behaviour should not change or only minimally change)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [x] There are changes to the (Java) code
• [ ] There are changes to the taclet rule base
• [ ] There are changes to the deployment/CI infrastructure (gradle, github, ...)
• [ ] Other:

Ensuring quality

• [ ] I made sure that introduced/changed code is well documented (javadoc and inline comments).
• [ ] I made sure that new/changed end-user features are well documented (https://github.com/KeYProject/key-docs).
• [ ] I added new test case(s) for new functionality.
• [x] I have tested the feature as follows: manual test (UI code)
• [ ] I have checked that runtime performance has not deteriorated.

Additional information and contact(s)

The contributions within this pull request are licensed under GPLv2 (only) for inclusion in KeY.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 4.54545% with 21 lines in your changes are missing coverage. Please review.

Project coverage is 37.85%. Comparing base (7254776) to head (d88c575). Report is 114 commits behind head on main.

:exclamation: Current head d88c575 differs from pull request most recent head 523a172. Consider uploading reports for the commit 523a172 to get more accurate results

Files	Patch %	Lines
...i/plugins/caching/actions/CopyReferencedProof.java	0.00%	19 Missing :warning:
...ka/ilkd/key/proof/reference/ReferenceSearcher.java	33.33%	2 Missing :warning:

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #3440      +/-   ##
============================================
- Coverage     37.86%   37.85%   -0.02%     
+ Complexity    17079    17043      -36     
============================================
  Files          2092     2082      -10     
  Lines        127596   127299     -297     
  Branches      21478    21442      -36     
============================================
- Hits          48316    48184     -132     
+ Misses        73355    73202     -153     
+ Partials       5925     5913      -12     

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[FliegendeWurst]

I nearly always get a dialog listing (only) the nodes where the caching failed (in the screenshot, actually two of the three goals are closed via cache):

I changed this dialog to list both successful matches and mismatches.

A bit unrelated, I have another small feature request: "Prune Proof" should work with goals that are closed by cache.

Done