tokens: restructure summary type breakdown in header
Replace flat Generate/Cogitate cost items with a two-row summary table in the tokens header card.
- Preserve the top-row overall summary metrics (Daily Total, Total Tokens, Requests, Avg/Segment)
- Add per-type columns for Cost, Tokens, Requests, and Avg/Req
- Update renderDashboard() to populate all per-type fields with zero-data fallbacks
- Remove redundant summary-type label classes and unreliable table padding-top styling