Summary

• fix strict yt-dlp exact selector construction by quoting format_id values in resolver chains
• skip PO token usage for exact format selections to avoid reduced format availability during strict matching
• preserve codec case in normalization so exact AV1 tuple matching remains valid

Validation

• CI/Coverage/Docker on dev are green for head 4edb767
• runtime checks confirm exact video/audio jobs now reach done instead of exact_selection_unavailable