refactor: standardize variable naming and file formatting

- Rename Quantity to quantity in BomItem for consistent naming convention
- Update references in MainModule to use lowercase quantity
- Add newlines at end of files for consistency
- Update vba_metadata.json with new source path and document module

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

VBA/ClassModules/BomExtractor.cls

@@ -481,4 +481,4 @@ Public Function GetErrorSummary() As String
         Next msg
         GetErrorSummary = result
     End If
-End Function
+End Function

VBA/ClassModules/BomItem.cls

@@ -12,7 +12,7 @@ Public RowNumber As Long        ' 行号
 Public Module As String         ' 模块
 Public code As String           ' 代号
 Public Name As String           ' 名称
-Public Quantity As Double       ' 数量
+Public quantity As Double       ' 数量
 Public SelectCondition As String ' 选择条件
 Public Remark As String         ' 备注
 Public category As String       ' 类别
@@ -46,7 +46,7 @@ Public Sub LoadFromRow(ws As Worksheet, row As Long)
     Me.Module = CStr(ws.Cells(row, 2).value)     ' B列: 模块
     Me.code = CStr(ws.Cells(row, 3).value)       ' C列: 代号
     Me.Name = CStr(ws.Cells(row, 4).value)       ' D列: 名称
-    Me.Quantity = CDbl(ws.Cells(row, 5).value)   ' E列: 数量
+    Me.quantity = CDbl(ws.Cells(row, 5).value)   ' E列: 数量
     Me.SelectCondition = CStr(ws.Cells(row, 6).value)  ' F列: 选择条件
     Me.Remark = CStr(ws.Cells(row, 7).value)     ' G列: 备注
     Me.category = CStr(ws.Cells(row, 8).value)   ' H列: 类别
@@ -85,4 +85,4 @@ Public Function ToString() As String
                " | 类别:" & Me.category & _
                " | 代号:" & Me.code & _
                " | 名称:" & Me.Name
-End Function
+End Function

VBA/ClassModules/ConditionEvaluator.cls

@@ -207,4 +207,4 @@ Private Function IsMatchedParentheses(str As String) As Boolean
     Next i
 
     IsMatchedParentheses = (depth = 0)
-End Function
+End Function

VBA/ClassModules/ProductModelParser.cls

@@ -231,4 +231,4 @@ Public Function GetAllConditions() As String
     Next key
 
     GetAllConditions = result
-End Function
+End Function