fix(usage): stop double-counting streaming usage at source

logUsage now only logs to console; DB write removed. Streaming usage is
recorded once via saveUsageStats (onStreamComplete), eliminating duplicate
usageHistory rows that inflated dashboard totals.

Co-authored-by: Cursor <cursoragent@cursor.com>

open-sse/utils/usageTracking.js

@@ -2,7 +2,6 @@
  * Token Usage Tracking - Extract, normalize, estimate and log token usage
  */
 
-import { saveRequestUsage, appendRequestLog } from "@/lib/usageDb.js";
 import { FORMATS } from "../translator/formats.js";
 
 // ANSI color codes
@@ -333,15 +332,4 @@ export function logUsage(provider, usage, model = null, connectionId = null, api
   if (reasoning) msg += ` | reasoning=${reasoning}`;
 
   console.log(msg);
-
-  // Save to usage DB
-  const tokens = {
-    prompt_tokens: inTokens,
-    completion_tokens: outTokens,
-    cache_read_input_tokens: cacheRead || 0,
-    cache_creation_input_tokens: cacheCreation || 0,
-    reasoning_tokens: reasoning || 0
-  };
-  saveRequestUsage({ model, provider, connectionId, tokens, apiKey: apiKey || undefined }).catch(() => { });
-  appendRequestLog({ model, provider, connectionId, tokens, status: "200 OK" }).catch(() => { });
 }