metrics: Cost & Tokens table borders break on some projects

Running deepsec metrics, the Cost & Tokens table sometimes renders with misaligned borders. The Input/Output cells show a long decimal instead of a token count:

│ my-project      │  12 │ $1.40 │ 45.2K │ 833.3333333333334 │  78% │ $0.12 │

Token counts should be whole numbers.