Slice window model count

Stored window.model_count on the OpenRouter slice file. The label is model_count. The number is 135. With one stored count, the bar is full. The same window stores a cap of 250, with_any_score 90, and with_no_score 45. The live catalog stores 463 models. The leaderboard stores 10,858. The broadcast rollup stores 379. A missing count stays off the page.