Align usage dashboard with CCSwitch

Filter request logs to model API calls and add request, provider, model, and settings tabs.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

internal/gateway/responses.go

@@ -38,6 +38,7 @@ func (s *Server) handleResponses(w http.ResponseWriter, r *http.Request) {
 	rec := recordFrom(r)
 	if provider.Protocol == config.ProtocolOpenAIResponses {
 		rec.update(func(e *LogEntry) {
+			e.Provider = provider.Name
 			e.Model = model
 			e.InputTokens = (len(body) + 3) / 4
 		})
@@ -57,6 +58,7 @@ func (s *Server) handleResponses(w http.ResponseWriter, r *http.Request) {
 	}
 
 	rec.update(func(e *LogEntry) {
+		e.Provider = provider.Name
 		e.Model = model
 		e.InputTokens = responses.EstimateTokens(chatReq)
 	})