Regenerate the Web families reference file (line_profile contract v2) #71

Since DataLab-Platform/Sigima#98, sigima.image.line_profile is in contract version 2. The Web families reference file (tests/fixtures/provenance/web_families.h5) still records it in version 1: the cross-edition tests refuse it as expected (unsupported_contract), so this operation is no longer actually replayed across editions from the Web file. The Desktop file was already regenerated in DataLab-Platform/DataLab#437.

Regenerate web_families.h5 with the pinned Sigima snapshot (Playwright, DLW_WRITE_PROVENANCE_FIXTURE=1), then copy it to DataLab (provenance_web_families.h5).