2026.1.0

Added:

• quick_index() now accepts a length_min parameter (default: 2.5 Å)
  to control the minimum unit cell length explored during indexing.
• Exposed ReflectionProfile methods (GetProfile, GetFullProfileWidth, XMLOutput, XMLInput) via Python bindings. Added unit tests.
• The binding to ReflectionProfile.GetProfile(x, xcenter, h, k, l) accepts python sequences / numpy arrays for the x argument, thanks to the helper function assignCrystVector.
• None.
• Expose PowderPattern.GetPowderPatternObsSigma and PowderPattern.SetPowderPatternObsSigma from objcryst
• Add AGENTS.md documenting contribution guidelines for AI coding agents
  (dependency chain, commit conventions, news-item policy, human-review
  requirement).
• Add support for Python 3.14.
• Exposed Radiation.GetLinearPolarRate(), Radiation.SetLinearPolarRate(),
  Radiation.GetClockWavelength(), and Radiation.GetClockRadiation() via
  Python bindings. Closes #38 <https://github.com/diffpy/pyobjcryst/issues/38>.
  Radiation.GetClockLinearPolarRate() is also bound and will be available once
  diffpy/libobjcryst picks up vincefn/objcryst PR #79 <https://github.com/vincefn/objcryst/pull/79>, which adds the dedicated
  polarisation clock and fixes the polarisation-correction recalculation trigger.

Changed:

• quick_index() default minimum unit cell length lowered from 3 Å to 2.5 Å,
  allowing correct indexing of compact structures such as α-Fe, B, or ZRNCl
  (issue #47 <https://github.com/diffpy/pyobjcryst/issues/47>_).
• None.
• None.

Deprecated:

• None.
• None.

Fixed:

• Exposed the correctly spelled ORTHORHOMBIC while preserving ORTHOROMBIC as temporary backend compatible alias
• Building with pip install . now uses sysconfig to locate `ObjCryst++`` libraries outside conda environments.
• Missing definition of ScatteringData in powderpatterndiffraction_ext.ccp
• Fixed PowderPattern.AddPowderPatternDiffraction() so a no-reflections failure does not leave a failed diffraction component attached to the powder pattern.
• quick_fit_profile(displ_transl=True) now correctly enables refinement of 2ThetaDispl and 2ThetaTransp by unfixing both parameters.

Removed:

• None.
• None.
• Remove support for Python 3.11.

Security:

• None.
• None.