feat: opus 4.6 woooo (#111)

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Reviewed-on: #111
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src-tauri/src/stats.rs

@@ -86,6 +86,8 @@ impl ContextWarning {
 /// Get the context window limit (in tokens) for a given model
 fn get_context_window_limit(model: &str) -> u64 {
     match model {
+        // Claude 4.6 family - 200K standard (1M beta available via header)
+        "claude-opus-4-6" => 200_000,
         // Claude 4.5 family - 200K standard context
         "claude-opus-4-5-20251101"
         | "claude-sonnet-4-5-20250929"
@@ -498,7 +500,10 @@ pub fn calculate_cost(
     cache_read_tokens: Option<u64>,
 ) -> f64 {
     let (input_price_per_million, output_price_per_million) = match model {
-        // Current generation (Claude 4.5)
+        // Current generation (Claude 4.6)
+        "claude-opus-4-6" => (5.0, 25.0),
+
+        // Previous generation (Claude 4.5)
         "claude-opus-4-5-20251101" => (5.0, 25.0),
         "claude-sonnet-4-5-20250929" => (3.0, 15.0),
         "claude-haiku-4-5-20251001" => (1.0, 5.0),