Correct Roblox artifact metadata

[abrignoni]

Summary

• make Roblox sample-data declarations match each artifact platform and path set
• give Windows wrappers explicit Windows sample metadata
• correct notification-history and credential-validity wording
• document the lack of a positive User Content sample
• update audited artifact metadata dates

Validation

• full macOS and Windows corpus runs completed without parser errors
• all 28 declared sample row counts matched generated TSV output
• platform/category/path metadata audit passed across all 29 Roblox artifacts
• 13 targeted tests passed
• changed-file pylint and diff checks passed

Scope

Runtime artifact modules only. Local profiles, tests, generated reports, and corpus data are excluded.