chore: sync model pricing from OpenRouter API

providers/~anthropic.toml

@@ -0,0 +1,18 @@
+# ~anthropic — auto-generated from OpenRouter API
+
+[provider]
+id = "~anthropic"
+display_name = "~Anthropic"
+api_key_env = "OPENROUTER_API_KEY"
+base_url = "https://openrouter.ai/api/v1"
+key_required = true
+
+[[models]]
+id = "claude-opus-latest"
+display_name = "Anthropic: Claude Opus Latest"
+tier = "frontier"
+context_window = 1000000
+max_output_tokens = 128000
+input_cost_per_m = 5.0
+output_cost_per_m = 25.0
+supports_streaming = true