[BUG]: ‘Monolithic' McStas/McXtrace Windows installers misses miniconda3\bin in path

[willend]

Describe the bug
Adrien Perrichon from ESS has reported issues running with the ‘Monolithic' McStas Windows installer and not being able to compile with NCrystal

Analysing the situation I found that C:\mccode-x.y.z\miniconda3\bin is missing in the *.bat / etc. path

Document steps to reproduce the bug
Steps to reproduce the behavior:

1. Download and install McStas-Metapackage-3.6.5-win64.exe
2. Run the NCrystal_example.instr
3. Compilation fails with:

mcrun -c NCrystal_example.instr --verbose
INFO: No output directory specified (--dir)
INFO: Using directory: "NCrystal_example_20260212_160611"
INFO: Regenerating c-file: NCrystal_example.c
WARNING: Full-path code-generator "C:\mcstas-3.6.5\bin\mcstas" not found!!
WARNING: Attempting replacement by "mcstas"
DEBUG: CMD: mcstas -t -o NCrystal_example.c NCrystal_example.instr

-----------------------------------------------------------

Generating single GPU kernel or single CPU section layout:
-> SPLIT N at component monochromator
-> SPLIT N at component powder_sample

-----------------------------------------------------------

Generating GPU/CPU -DFUNNEL layout:
Component monochromator is NOACC, CPUONLY=1
-> FUNNEL mode enabled, SPLIT within buffer.
-> SPLIT within buffer at component monochromator
-> GPU kernel from component mono_out
Component powder_sample is NOACC, CPUONLY=1
-> FUNNEL mode enabled, SPLIT within buffer.
-> SPLIT within buffer at component powder_sample
-> GPU kernel from component powder_pattern_detc

-----------------------------------------------------------
CFLAGS= @NCRYSTALFLAGS@ -DFUNNEL
DEBUG: CMD: mcstas finished
INFO: Recompiling: NCrystal_example.exe
   --> launching cmd: ncrystal-config --show libdir
Traceback (most recent call last):
  File "C:\mcstas-3.6.5\bin\\../lib/tools\Python\mcrun\mcrun.py", line 654, in <module>
    main()
    ~~~~^^
  File "C:\mcstas-3.6.5\bin\\../lib/tools\Python\mcrun\mcrun.py", line 540, in main
    mcstas.prepare(options)
    ~~~~~~~~~~~~~~^^^^^^^^^
  File "C:\mcstas-3.6.5\lib\tools\Python\mcrun\mccode.py", line 305, in prepare
    flags = mccodelib.cflags.evaluate_dependency_str(flags, options.verbose)
  File "C:\mcstas-3.6.5\lib\tools\Python\mcrun\..\mccodelib\cflags.py", line 99, in evaluate_dependency_str
    s = evalmarker( s, s_cmd, evalfct_cmd )
  File "C:\mcstas-3.6.5\lib\tools\Python\mcrun\..\mccodelib\cflags.py", line 55, in evalmarker
    return before + evalfct(content) + evalmarker(after,startmarker,evalfct)
                    ~~~~~~~^^^^^^^^^
  File "C:\mcstas-3.6.5\lib\tools\Python\mcrun\..\mccodelib\cflags.py", line 90, in evalfct_cmd
    raise RuntimeError(errmsg())
RuntimeError: Errors encountered while executing cmd: ncrystal-config --show libdir

Workaround
Adding to the shell path resolves the issue:

set PATH=%PATH%;C:\mcstas-3.6.5\miniconda3\bin
mcrun -c NCrystal_example.instr
INFO: No output directory specified (--dir)
INFO: Using directory: "NCrystal_example_20260212_160725"
INFO: Regenerating c-file: NCrystal_example.c
WARNING: Full-path code-generator "C:\mcstas-3.6.5\bin\mcstas" not found!!
WARNING: Attempting replacement by "mcstas"

-----------------------------------------------------------

Generating single GPU kernel or single CPU section layout:
-> SPLIT N at component monochromator
-> SPLIT N at component powder_sample

-----------------------------------------------------------

Generating GPU/CPU -DFUNNEL layout:
Component monochromator is NOACC, CPUONLY=1
-> FUNNEL mode enabled, SPLIT within buffer.
-> SPLIT within buffer at component monochromator
-> GPU kernel from component mono_out
Component powder_sample is NOACC, CPUONLY=1
-> FUNNEL mode enabled, SPLIT within buffer.
-> SPLIT within buffer at component powder_sample
-> GPU kernel from component powder_pattern_detc

-----------------------------------------------------------
CFLAGS= @NCRYSTALFLAGS@ -DFUNNEL
INFO: Recompiling: NCrystal_example.exe
INFO: ===
Instrument parameters for NCrystal_example (NCrystal_example.instr)
Set value of instrument parameter sample_cfg (string) [default='Y2O3_sg206_Yttrium_Oxide.ncmat;density=0.9x']:

[NCrystal_example] Initialize
NCrystal: McStas sample component(s) are using version 4.2.12 of the NCrystal library.
*** TRACE end ***

Save [NCrystal_example]
Detector: powder_pattern_detc_I=5.92655e-011 powder_pattern_detc_ERR=1.82705e-013 powder_pattern_detc_N=105307 "powder_pattern_detc.dat"

Finally [NCrystal_example: NCrystal_example_20260212_160725]. Time: 8 [s]
INFO: Placing instr file copy NCrystal_example.instr in dataset NCrystal_example_20260212_160725
INFO: Placing generated c-code copy NCrystal_example.c in dataset NCrystal_example_20260212_160725

OS and McStas/McXtrace version (please complete the following information):

• OS: [Windows 11]
• McCode variant [probably both of McStas, McXtrace]
• Version [3.6.5 ‘Monolithic installer only']

Additional context
Likely just a matter of a small adjustment in Locations.cmake / PlatformDefaults.cmake