Scrub private infrastructure detail and move the GPU harnesses out

The Content Seal manifest named the production GPU worker in its provenance
column and in two row keys, several docstrings described their sources as user
uploads from the private corpus, and that corpus was called by the storage
product holding it. Each is now what a public reader can check: a pipeline and
strength, material that is not publication-cleared, and a private corpus. The
corpus test follows the renamed rows. Deployment and tier detail goes the same
way, since which backend each hosting tier can afford is a product decision,
not a library fact.

Twelve harnesses that need a cloud GPU account leave scripts/. The research
pages that cite their findings name them as harnesses kept outside this
repository and stop implying a reader can rerun them; the tracked inputs and
recorded verdicts remain the durable record, and the offline analysis step
stays here with its test. A development invariant states the rule so the next
harness is not added back.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

data/evaluations/engine-selection/README.md

@@ -49,8 +49,8 @@ strengths. The tracked oracle/carrier inputs remain in their canonical homes:
   `data/contentseal/manifest.csv`.
 
 There is no tracked, publication-cleared Microsoft InvisMark carrier yet. The
-three Paint sources used by the earlier calibration are user uploads and remain
-outside git. A Microsoft row may be added only from a newly generated or
+three Paint sources used by the earlier calibration are not publication-cleared
+and remain outside git. A Microsoft row may be added only from a newly generated or
 otherwise publication-cleared source, with a pixel-identical metadata-stripped
 control that remains positive in Microsoft's detector.