v0.1.1

Fixed

• HEDM stitching noise model is now physically consistent. Synthetic
  measurement error was previously injected as a single fractional noise_level
  applied multiplicatively to all of X, Y, Z, GrainRadius, and the three Euler
  angles. For centroids this made the absolute error scale with distance from
  the origin (zero at the origin, large far away) and put it in different units
  than the stitcher's absolute position_tolerance. Noise is now split into
  three independent, physically meaningful channels.
• Fixed a latent cost-normalization bug in ScanStitchingComparison: the -1
  "disable" sentinel was used as a divisor, which could invert the sign of a
  weighted cost term. Normalizers now guard on > 0, matching
  RegionBaseStitching.

Changed

CrystalGenerator.write_to_csv and hedm_zscan no longer accept
apply_noise, apply_noise_method, or noise_level. Use instead:

Old	New
noise_level (fractional, all columns)	position_noise_std (absolute, length units, additive on X/Y/Z)
	orientation_noise_std (degrees, proper misorientation)
	radius_noise (relative fraction of GrainRadius)
apply_noise=True/False	set any std > 0 to enable; all-zero = noiseless
(none)	noise_seed for reproducible noise

Each channel is applied only when its value is > 0, so the default is
noiseless (equivalent to the old apply_noise=False).

Added

• orientation_helper.perturb_orientation(euler, sigma_deg, ...): applies a
  proper random misorientation of a given angular std about a uniformly random
  axis (gimbal-free), replacing the old per-Euler fractional perturbation.

Migration

# before
cg.hedm_zscan(..., apply_noise=True, noise_level=0.01)

# after (physical units; tune to your experiment)
cg.hedm_zscan(
    ...,
    position_noise_std=3.0,      # micrometers
    orientation_noise_std=0.5,   # degrees
    radius_noise=0.05,           # 5% relative
    noise_seed=42,
)