feat(amulegui): wire the Kad "More" search button over EC - #573

Completes the "More" half of #571. aMuleGUI's search "More" button was permanently greyed because the remote-GUI CSearchListRem stubbed IsKadSearch/RequestMoreResults to always return false (no local Kad layer). This wires it over EC, matching the monolithic GUI.

Per-id search kind (fixes a latent scalar bug). The EC progress reply's EC_TAG_SEARCH_LIFECYCLE_KIND was the scalar m_searchType (the most-recently-started search's type), so with several searches open it was wrong for any older tab of a different type — cosmetic for amuleapi/amuleweb, but it made a reliable per-tab Kad check impossible. CSearchList now records each search's kind by id and the reply reports GetSearchLifecycleKindById(sid).

Enable — gated on the progress lifecycle, no new status. amuleGUI caches kind == Kad && state == RUNNING per search from each progress reply and returns it from IsKadSearch; the monolithic GUI gets the same live gate in RefreshVisibleTabProgress. So "More" is enabled only while a Kad search is running and greys out on completion, in both GUIs.

Action. New EC_OP_SEARCH_REQUEST_MORE (fire-and-forget, like the per-id stop): RequestMoreResults(sid) sends it with the selected tab's EC_TAG_SEARCH_ID; the daemon widens that Kad search. Multi-search-correct — it addresses the selected tab by id.

Single source of truth. The action and its outcome logging live in one place — CSearchList::RequestMoreResults logs "requested wider results" / "no peer left to reask (cap reached)"; the monolithic GUI and the daemon (for a remote request) both reach it. EC codes hand-added to both ECCodes.abstract and the committed ECCodes.h.

Verified by building amule, amulegui, and amuled.