Scrub legacy blinding vocabulary (pre-Smokescreen blind A/B/C) #312

Three pre-Smokescreen "blind" strata survive in the code and collide with Smokescreen blinding (#241) vocabulary:

• CosmologyValidation.blind — redshift-path blind A/B/C suffix substitution (core.py)
• the blind wildcard on the pseudo_cl rules — glass-mock A/B/C variant, baked into on-disk filenames (kept as-is in cosmo_val + Snakemake migration to the SACC writers (PRD #241 row 4) #251 by ruling; comments mark the distinction)
• blind=A_… tags in legacy product filenames

Scrub them once the SACC/blinding stack (#251/#253/#255) is merged — this gates the first real assembly run, so no real product is made while two blinding vocabularies coexist: retire the legacy catalogue-blind path, rename or retire the mock-variant wildcard where on-disk compatibility allows, and unify stem/wildcard construction so every pseudo-Cl variant uses the same path-building convention (the new pseudo_cl_analysis stem currently differs from the wildcarded mock rules). Deliberately out of scope for #251/#253.

— Claude (fable) on behalf of Cail.