Migrate tests/test_floss.py to npt.assert_allclose

[viknesh-ai]

Related to #1175

Covers tests/test_floss.py (26 call sites). Renamed comp to cmp, flipped every call to (cmp, ref) order.

Only two of the four values compared per site needed a float64 cast: ref_P/ref_I come from slicing stump()/aamp() output, which is dtype=object (mixes the distance and index columns), same issue as the earlier files. ref_cac_1d and ref_T are already clean, so those stayed uncast.

12/12 passing locally in both normal and CI-equivalent (JIT-disabled, CUDA-simulated) modes.

To Do List

• assert_almost_equal -> assert_allclose
• no rtol=0
• actual, desired order (cmp first, ref second)
• atol=1.5e-07 literal - no decimal=/config references in this file
• cmp not comp
• ref_/cmp_ naming, casted only where the source is genuinely dtype=object

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[gitnotebooks]

Review these changes at https://app.gitnotebooks.com/stumpy-dev/stumpy/pull/1189

[viknesh-ai]

@seanlaw next file in the split — same conventions as the previous PRs. Ready for review whenever you have time.