fix(tests): keep the offline gate hermetic for model-fallback tests #388

Job	Run time
browser accessibility smoke	1m 6s
test + lint (full offline stack) (3.10)	1m 11s
docker smoke — path gate	5s
core floor (numpy-only, Python 3.9)	30s
build + install wheel	28s
test + lint (full offline stack) (3.11)	49s
test + lint (full offline stack) (3.12)	49s
docker build + health smoke	0s
	4m 58s

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