fix(search): remove unused SEARCH_THINKING_BUDGET constants from search module

Author: NoeFabris

src/plugin/search.ts

@@ -10,8 +10,6 @@ import {
   ANTIGRAVITY_ENDPOINT,
   ANTIGRAVITY_HEADERS,
   SEARCH_MODEL,
-  SEARCH_THINKING_BUDGET_DEEP,
-  SEARCH_THINKING_BUDGET_FAST,
   SEARCH_TIMEOUT_MS,
   SEARCH_SYSTEM_INSTRUCTION,
 } from "../constants";