Avoid diagonal-only hypertoroidal particle initialization

[FlorianPfaff]

Bug

For dim > 1, HypertoroidalParticleFilter tiled the same one-dimensional angular grid into every coordinate. Every initial particle therefore satisfied

x_1 = x_2 = ... = x_dim

The nominally uninformative initial particle set was confined to a diagonal submanifold of the torus and encoded perfect artificial dependence between angular coordinates. For example, the empirical first-harmonic dependence |E[exp(i (x_1 - x_2))]| was exactly 1.0.

Fix

Initialize multidimensional filters with a deterministic, centered Latin-hypercube design:

• one evenly spaced angular sample per marginal bin;
• reproducible construction that does not consume the global random stream;
• joint support no longer collapsed to the diagonal;
• the existing one-dimensional equidistant initialization remains unchanged.

Regression coverage

Add a focused three-dimensional constructor test that verifies:

• the particle matrix has the requested shape;
• the first two coordinates are not identical particle by particle;
• every angular marginal retains uniform wrapped spacing.

Validation

• reproduced the old joint-dependence magnitude as 1.0;
• the 32-particle replacement gives approximately 0.0953 for the same diagnostic;
• the focused Latin-hypercube regression passed locally;
• the modified implementation passes python -m py_compile;
• branch comparison: 2 commits ahead, 0 behind main;
• diff is limited to the hypertoroidal particle initializer and its existing test module.

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[github-actions]

✅MegaLinter analysis: Success

Descriptor	Linter	Files	Fixed	Errors	Warnings	Elapsed time
✅ COPYPASTE	jscpd	yes		no	no	27.22s
✅ JSON	prettier	7	0	0	0	1.02s
✅ JSON	v8r	7		0	0	4.08s
✅ MARKDOWN	markdownlint	68	0	0	0	1.83s
✅ MARKDOWN	markdown-table-formatter	68	0	0	0	0.86s
✅ PYTHON	black	1865	87	0	0	91.19s
✅ PYTHON	isort	1865	140	0	0	2.76s
✅ REPOSITORY	betterleaks	yes		no	no	2.56s
✅ REPOSITORY	checkov	yes		no	no	52.51s
✅ REPOSITORY	gitleaks	yes		no	no	17.73s
✅ REPOSITORY	git_diff	yes		no	no	0.33s
✅ REPOSITORY	secretlint	yes		no	no	83.69s
✅ REPOSITORY	syft	yes		no	no	5.62s
✅ REPOSITORY	trivy-sbom	yes		no	no	6.67s
✅ REPOSITORY	trufflehog	yes		no	no	30.5s
✅ YAML	prettier	11	0	0	0	0.74s
✅ YAML	v8r	11		0	0	13.09s
✅ YAML	yamllint	11		0	0	0.54s

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