chore: add buildOutput RTK filter, drop legacy cloud sync, internal cleanup

- feat(rtk): buildOutput filter + autodetect for npm/yarn/cargo logs
- chore: remove unused cloud sync module and related routes
- ui: hide deprecated providers (qwen, iflow, antigravity)
- chore: minor tray/cli/internal adjustments

open-sse/rtk/constants.js

@@ -50,5 +50,6 @@ export const FILTERS = {
   DEDUP_LOG: "dedup-log",
   SMART_TRUNCATE: "smart-truncate",
   READ_NUMBERED: "read-numbered",
-  SEARCH_LIST: "search-list"
+  SEARCH_LIST: "search-list",
+  BUILD_OUTPUT: "build-output"
 };