chore(sync): update cost ovhcloud model qwen*27b - #7056

Action items

• [low] [possible mistake] providers/ovhcloud/models/qwen3.6-27b.toml:19 - Check: Material cost updates should cite direct provider pricing/docs. Why: The PR body is empty while both models change billed rates (including qwen3.8-27b from 0/0 to paid). Without a mapped source, the new USD/MTok values cannot be reviewed. Action: Add PR-body citations to OVHcloud pricing/catalog (or sync output) stating what each URL supports for these two models’ input/output rates.
• [low] [possible mistake] providers/ovhcloud/models/qwen3.8-27b.toml:6 - Check: Leading comments must stay accurate after cost changes. Why: The header still says blank catalog rates default to zero, but this change sets non-zero cost. That will mislead later sync/edits. Action: Update or remove the blank-rate note and, if prices came from the catalog/API, document that source in the leading comment block.