ax(mining): fix test naming and comment style in dual_mining_test.go

Rename flat test functions to TestFilename_Function_{Good,Bad,Ugly} pattern
and replace prose description comments with usage-example comments per AX
principles 1 and 2.

Co-Authored-By: Charon <charon@lethean.io>

pkg/mining/dual_mining_test.go

@@ -6,9 +6,8 @@ import (
 	"time"
 )
 
-// TestDualMiningCPUAndGPU tests running CPU and GPU mining together
-// This test requires XMRig installed and a GPU with OpenCL support
-func TestDualMiningCPUAndGPU(t *testing.T) {
+// manager.StartMiner(ctx, "xmrig", &Config{GPUEnabled: true, OpenCL: true, Devices: "0"})
+func TestDualMining_CPUAndGPU_Good(t *testing.T) {
 	if testing.Short() {
 		t.Skip("Skipping dual mining test in short mode")
 	}
@@ -73,8 +72,8 @@ func TestDualMiningCPUAndGPU(t *testing.T) {
 	manager.StopMiner(context.Background(), minerInstance.GetName())
 }
 
-// TestGPUDeviceSelection tests that GPU mining requires explicit device selection
-func TestGPUDeviceSelection(t *testing.T) {
+// miner.createConfig(&Config{GPUEnabled: true, OpenCL: true}) // no Devices → GPU disabled
+func TestDualMining_GPUDeviceSelection_Bad(t *testing.T) {
 	tmpDir := t.TempDir()
 
 	miner := &XMRigMiner{