feat: 휴가 관리 화면 구현 (휠 다이얼 연차 설정)

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

app/src/main/java/com/example/shiftalarm/FragmentSettingsLab.kt

@@ -4,8 +4,11 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import android.widget.Toast
 import androidx.fragment.app.Fragment
+import androidx.lifecycle.lifecycleScope
 import com.example.shiftalarm.databinding.FragmentSettingsLabBinding
+import kotlinx.coroutines.launch
 
 class FragmentSettingsLab : Fragment() {
 
@@ -20,6 +23,56 @@ class FragmentSettingsLab : Fragment() {
         return binding.root
     }
 
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+        
+        setupNumberPicker()
+        loadAnnualLeave()
+        setupSaveButton()
+    }
+
+    private fun setupNumberPicker() {
+        binding.npTotalDays.apply {
+            minValue = 1
+            maxValue = 25
+            wrapSelectorWheel = false
+        }
+    }
+
+    private fun loadAnnualLeave() {
+        lifecycleScope.launch {
+            val repo = ShiftRepository(requireContext())
+            
+            val annualLeave = repo.getAnnualLeave()
+            annualLeave?.let {
+                binding.npTotalDays.value = it.totalDays.toInt()
+                binding.tvRemainingDays.text = String.format("%.1f", it.remainingDays)
+            } ?: run {
+                // Default: 15 days
+                binding.npTotalDays.value = 15
+                binding.tvRemainingDays.text = "15.0"
+            }
+        }
+    }
+
+    private fun setupSaveButton() {
+        binding.btnSaveAnnualLeave.setOnClickListener {
+            val totalDays = binding.npTotalDays.value.toFloat()
+            
+            lifecycleScope.launch {
+                val repo = ShiftRepository(requireContext())
+                
+                repo.recalculateAndSaveAnnualLeave(totalDays)
+                
+                val updated = repo.getAnnualLeave()
+                updated?.let {
+                    binding.tvRemainingDays.text = String.format("%.1f", it.remainingDays)
+                    Toast.makeText(requireContext(), "연차가 저장되었습니다. (남은 연차: ${String.format("%.1f", it.remainingDays)}일)", Toast.LENGTH_SHORT).show()
+                }
+            }
+        }
+    }
+
     override fun onDestroyView() {
         super.onDestroyView()
         _binding = null