v0.8.1 - Display Input/Output tokens

🔧 Display

wtk gain now shows Input tokens / Output tokens lines alongside Input chars / Output chars when cl100k data is present:

Total commands:    3
Input chars:       3.8K
Output chars:      1.5K
Chars saved:       2.3K (60.2%)
Input tokens:      1.1K
Output tokens:     556
Tokens saved:      516 (48.1%) (2/3 rows, cl100k)

Real numbers reveal the chars/4 heuristic gap — chars saved 60.2% but real token savings only 48.1% on this sample.

Full Changelog: v0.8.0...v0.8.1