Add nowritefile parameter to all Union loggers and abs_loggers

[mads-bertelsen-agentic]

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Please describe what your PR is adding in terms of features or bugfixes:

The nowritefile parameter, already standard for monitors, skips writing output data to disk when set. This adds the same feature to all Union logger and abs_logger components: a new int nowritefile=0 setting parameter, a documentation line under %P, and the save section wrapped in an if (!nowritefile) statement.

Union_abs_logger_nD already had the parameter and inherits the if-statement from Monitor_nD through SAVE INHERIT; its documentation line was corrected from 'Not functional for Union version'.

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UTM Virtual machine OS X 14.6.1 (23G93)

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[willend]

Hi @mads-bertelsen-agentic, @mads-bertelsen

The Windows test is failing - very likely due to a too long path / filename.

I've dug out just the relevant portion of the test output in the attached zip-file for convenience
run_mctest.zip

The failing instruments all seem to error in compilation with this type of output:

more ....(long path)/Unit_test_abs_logger_1D_space_event/compile_stdout.txt 
INFO: No output directory specified (--dir)
INFO: Using directory: "Unit_test_abs_logger_1D_space_event_20260828_135650"
INFO: Regenerating c-file: Unit_test_abs_logger_1D_space_event.c
WARNING: Full-path code-generator "C:\Users\runneradmin\micromamba\envs\mcstas\bin\mcstas" not found!!
WARNING: Attempting replacement by "mcstas"
DEBUG: CMD: mcstas -t -o Unit_test_abs_logger_1D_space_event.c Unit_test_abs_logger_1D_space_event.instr


Fatal error: mcstas: Instrument definition file `Unit_test_abs_logger_1D_space_event.instr' not found


Program aborted.
INFO: call to mcstas failed with Command 'mcstas -t -o Unit_test_abs_logger_1D_space_event.c Unit_test_abs_logger_1D_space_event.instr' returned non-zero exit status 1.
ERROR: Code generation failed for instrument Unit_test_abs_logger_1D_space_event.instr using code generator mcstas

Part of the issue comes from a requirement to make output folders unique (including details on platform and execution conditions) - and while I can correct / solve part of the problem by adjusting mctest itself - these instrument filenames / component names are themselves also getting very long... :-)

(I suggest stylistic changes along the lines of e.g. Unit_test -> Unittest, abs_logger -> abslog, space -> xyz, event -> list)

[willend]

Rebased PR branch to current state of main @mads-bertelsen-agentic @mads-bertelsen

[willend]

@mads-bertelsen-agentic, @mads-bertelsen there is in fact a good chance the rebase will let the tests to run through - I'd still like the stylistic filename changes..

[mads-bertelsen]

Great catch! Didn’t think of that long filename issue even though I have encountered it on windows systems before.

Happy to shorten the names of the test instruments, changing the component names themselves would require updating a lot of instruments, in repo and outside, so hope it’s acceptable to leave those as they are.

[willend]

@mads-bertelsen another complexity occurred - testing multiple comps with similar names easily leads to folder-clashes in the CI - but have nailed it now I think...