macOS port: build, rendering, daemon, and mining fixes

Build & setup:
- Fix setup.sh and build.sh for macOS (bundle daemon, xmrig, sapling params, asmap.dat into .app)
- Fix CMakeLists.txt libsodium linking for macOS
- Fix incbin.h to use __DATA,__const section on macOS
- Remove vendored libsodium-1.0.18 source tree (use fetch script instead)
- Remove prebuilt-binaries/xmrig (replaced by xmrig-hac)
- Add .DS_Store to .gitignore

Rendering & UI:
- Use GLSL #version 150 and OpenGL 3.2 Core Profile on macOS
- Force dpiScale=1.0 on macOS to fix Retina double-scaling
- Set default window/UI opacity to 100% on Mac/Linux
- Add scroll fade shader guard for macOS GL compatibility
- Add ImGui error recovery around render loop and mining tab

Daemon & bootstrap:
- Fix getDragonXDataDir() to return ~/Library/Application Support/Hush/DRAGONX/ on macOS
- Fix isPortInUse() with connect() fallback (no /proc/net/tcp on macOS)
- Increase daemon watchdog timeout from 3s to 15s
- Add daemon status indicator (colored dot + label) in wizard bootstrap phases

Mining tab:
- Fix EmbeddedDaemon::getMemoryUsageMB() crash on macOS (was using Linux /proc)
- Fix XmrigManager::getMemoryUsageMB() to use ps on macOS instead of /proc
- Restructure RenderMiningTab with wrapper pattern for exception safety
- Fix default pool URL to include port (pool.dragonx.is:3433)

src/daemon/xmrig_manager.h

@@ -55,7 +55,7 @@ public:
 
     /// User-facing config (maps 1:1 to UI fields / Settings)
     struct Config {
-        std::string pool_url        = "pool.dragonx.is";
+        std::string pool_url        = "pool.dragonx.is:3433";
         std::string wallet_address;
         std::string worker_name     = "x";
         std::string algo            = "rx/hush";