chore(setup): build miner from DragonX/drg-xmrig and rename staging dir

setup.sh now clones/builds the miner from git.dragonx.is/DragonX/drg-xmrig
(was dragonx/xmrig-hac), and the prebuilt staging dir is renamed
prebuilt-binaries/xmrig-hac -> prebuilt-binaries/drg-xmrig across build.sh, the
legacy Windows build script, .gitignore and README.

Also aligns setup.sh's section-8 directory list with section 7 (it previously
used a bare "xmrig" token, creating a stray empty prebuilt-binaries/xmrig/),
and updates the xmrig_manager.cpp header comment.

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

setup.sh

@@ -684,11 +684,13 @@ if [[ "$STALE_DAEMON" -eq 1 ]]; then
     warn "  Linux: ./setup.sh   ·   Windows: ./setup.sh --win   ·   macOS: ./setup.sh --mac"
 fi
 
-# ── 7. xmrig-hac (mining binary) ────────────────────────────────────────────
-header "xmrig-hac Mining Binary"
+# ── 7. drg-xmrig (mining binary) ────────────────────────────────────────────
+header "drg-xmrig Mining Binary"
 
-XMRIG_SRC="$PROJECT_DIR/external/xmrig-hac"
-XMRIG_PREBUILT="$PROJECT_DIR/prebuilt-binaries/xmrig-hac"
+XMRIG_SRC="$PROJECT_DIR/external/drg-xmrig"
+# Output dir bundled by build.sh (Linux zip, AppImage, Windows embed, mac .app)
+# and scripts/legacy/build-windows.sh — keep this path in sync with those.
+XMRIG_PREBUILT="$PROJECT_DIR/prebuilt-binaries/drg-xmrig"
 
 # Clean previous prebuilt xmrig binaries so we always rebuild
 # Only clean the binary for the platform(s) we are actually building,
@@ -700,14 +702,14 @@ if ! $CHECK_ONLY; then
     fi
 fi
 
-# Helper: clone xmrig-hac if not present
+# Helper: clone drg-xmrig if not present
 clone_xmrig_if_needed() {
     if [[ ! -d "$XMRIG_SRC" ]]; then
-        info "Cloning xmrig-hac..."
-        git clone https://git.dragonx.is/dragonx/xmrig-hac.git "$XMRIG_SRC"
+        info "Cloning drg-xmrig..."
+        git clone https://git.dragonx.is/DragonX/drg-xmrig.git "$XMRIG_SRC"
     else
-        ok "xmrig-hac source already present"
-        info "Pulling latest xmrig-hac..."
+        ok "drg-xmrig source already present"
+        info "Pulling latest drg-xmrig..."
         (cd "$XMRIG_SRC" && git pull --ff-only 2>/dev/null || true)
     fi
 }
@@ -728,15 +730,15 @@ else
     rm -rf "$XMRIG_SRC/build"
 
     # Build dependencies (libuv, hwloc, openssl)
-    info "Building xmrig-hac dependencies (libuv, hwloc, openssl)..."
+    info "Building drg-xmrig dependencies (libuv, hwloc, openssl)..."
     (
         cd "$XMRIG_SRC/scripts"
         sh build_deps.sh
     )
-    ok "xmrig-hac dependencies built"
+    ok "drg-xmrig dependencies built"
 
     # Build xmrig
-    info "Building xmrig-hac (Linux)..."
+    info "Building drg-xmrig (Linux)..."
     mkdir -p "$XMRIG_SRC/build"
     (
         cd "$XMRIG_SRC/build"
@@ -753,7 +755,7 @@ else
     mkdir -p "$XMRIG_PREBUILT"
     if [[ -f "$XMRIG_SRC/build/xmrig" ]]; then
         cp "$XMRIG_SRC/build/xmrig" "$XMRIG_LINUX"
-        ok "xmrig (Linux) built and installed to prebuilt-binaries/xmrig-hac/"
+        ok "xmrig (Linux) built and installed to prebuilt-binaries/drg-xmrig/"
     else
         err "xmrig (Linux) build failed — binary not found"
         MISSING=$((MISSING + 1))
@@ -777,7 +779,7 @@ else
     # Clean previous Windows build
     rm -rf "$XMRIG_SRC/build-windows"
 
-    info "Building xmrig-hac (Windows cross-compile)..."
+    info "Building drg-xmrig (Windows cross-compile)..."
     (
         cd "$XMRIG_SRC/scripts"
         bash build_windows.sh
@@ -787,7 +789,7 @@ else
     mkdir -p "$XMRIG_PREBUILT"
     if [[ -f "$XMRIG_SRC/build-windows/xmrig.exe" ]]; then
         cp "$XMRIG_SRC/build-windows/xmrig.exe" "$XMRIG_WIN"
-        ok "xmrig.exe (Windows) built and installed to prebuilt-binaries/xmrig-hac/"
+        ok "xmrig.exe (Windows) built and installed to prebuilt-binaries/drg-xmrig/"
     else
         err "xmrig.exe (Windows) build failed — binary not found"
         MISSING=$((MISSING + 1))
@@ -797,7 +799,7 @@ fi
 # ── 8. Binary directories ───────────────────────────────────────────────────
 header "Binary Directories"
 
-for platform in dragonxd-linux dragonxd-win dragonxd-mac xmrig; do
+for platform in dragonxd-linux dragonxd-win dragonxd-mac drg-xmrig; do
     dir="$PROJECT_DIR/prebuilt-binaries/$platform"
     if [[ -d "$dir" ]]; then
         # Count actual files (not .gitkeep)