feat(mining): auto-balance driver, per-pool algo, live miner version

- app: periodic weighted-random auto-balance of the pool while pool-mining
  (~30-min cadence; restarts the miner only when the pick actually changes),
  plus snapshot + refresh accessors for the UI.
- app_network: resolve the xmrig algo per pool at start (pool.dragonx.cc =
  rx/dragonx, pool.dragonx.is = rx/hush; custom hosts keep the setting).
- xmrig_manager: schema-aware pool-side hashrate readout (fixes a silent 0 for
  Miningcore pools); expose the running miner's version from its HTTP API and a
  cached `xmrig --version` detection so the UI can show it before mining.
- wallet_state: carry the running miner's version.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app_network.cpp

@@ -38,6 +38,7 @@
 #include "daemon/daemon_controller.h"
 #include "daemon/embedded_daemon.h"
 #include "daemon/xmrig_manager.h"
+#include "util/pool_registry.h"
 #include "ui/notifications.h"
 #include "default_banlist_embedded.h"
 #include "util/amount_format.h"
@@ -1718,7 +1719,9 @@ void App::startPoolMining(int threads)
     daemon::XmrigManager::Config cfg;
     cfg.pool_url       = settings_->getPoolUrl();
     cfg.worker_name    = settings_->getPoolWorker();
-    cfg.algo           = settings_->getPoolAlgo();
+    // The algo follows the pool: official pools use their own algo (pool.dragonx.cc
+    // needs rx/dragonx, pool.dragonx.is rx/hush); custom hosts keep the setting.
+    cfg.algo           = util::resolvePoolAlgo(cfg.pool_url, settings_->getPoolAlgo());
     cfg.threads        = threads;  // Use the same thread selection as solo mining
     cfg.tls            = settings_->getPoolTls();
     cfg.hugepages      = settings_->getPoolHugepages();