fix(windows): initialize visual defaults safely

lib/core/base.ps1

@@ -47,24 +47,36 @@ $script:DefaultIcons = @{
     Trash    = [char]0x2718  # ✘ (trash substitute)
 }
 
-function Initialize-MoleVisualDefaults {
-    if (-not ($script:Colors -is [hashtable])) {
-        $script:Colors = @{}
+function Get-OrCreateScriptHashtable {
+    param(
+        [Parameter(Mandatory)]
+        [string]$Name
+    )
+
+    $existing = Get-Variable -Name $Name -Scope Script -ErrorAction SilentlyContinue
+    if ($existing -and $existing.Value -is [hashtable]) {
+        return $existing.Value
     }
 
+    $table = @{}
+    Set-Variable -Name $Name -Scope Script -Value $table
+    return $table
+}
+
+function Initialize-MoleVisualDefaults {
+    $colors = Get-OrCreateScriptHashtable -Name "Colors"
+
     foreach ($entry in $script:DefaultColors.GetEnumerator()) {
-        if (-not $script:Colors.ContainsKey($entry.Key)) {
-            $script:Colors[$entry.Key] = $entry.Value
+        if (-not $colors.ContainsKey($entry.Key)) {
+            $colors[$entry.Key] = $entry.Value
         }
     }
 
-    if (-not ($script:Icons -is [hashtable])) {
-        $script:Icons = @{}
-    }
+    $icons = Get-OrCreateScriptHashtable -Name "Icons"
 
     foreach ($entry in $script:DefaultIcons.GetEnumerator()) {
-        if (-not $script:Icons.ContainsKey($entry.Key)) {
-            $script:Icons[$entry.Key] = $entry.Value
+        if (-not $icons.ContainsKey($entry.Key)) {
+            $icons[$entry.Key] = $entry.Value
         }
     }
 }

tests/Commands.Tests.ps1

@@ -6,6 +6,7 @@ BeforeAll {
     $script:WindowsDir = Split-Path -Parent $PSScriptRoot
     $script:BinDir = Join-Path $script:WindowsDir "bin"
     $script:InstallScript = Join-Path $script:WindowsDir "install.ps1"
+    $script:VisualDefaultsErrorPattern = 'property ''Solid'' cannot be found|找不到属性.?Solid|VariableIsUndefined|\$script:Colors'
 }
 
 Describe "Clean Command" {
@@ -49,7 +50,7 @@ Describe "Clean Command" {
             Stop-Job $job -ErrorAction SilentlyContinue
             Remove-Job $job -Force -ErrorAction SilentlyContinue
 
-            $output | Should -Not -Match "property 'Solid' cannot be found|找不到属性.?Solid"
+            $output | Should -Not -Match $script:VisualDefaultsErrorPattern
         }
     }
 }
@@ -175,7 +176,9 @@ Describe "Main Entry Point" {
         It "Should show version without error" {
             $result = & powershell -ExecutionPolicy Bypass -File $script:MolePath -Version 2>&1
             $result | Should -Not -BeNullOrEmpty
-            $result -join "`n" | Should -Match "Mole|v\d+\.\d+"
+            $output = $result -join "`n"
+            $output | Should -Not -Match $script:VisualDefaultsErrorPattern
+            $output | Should -Match "Mole|v\d+\.\d+"
         }
 
         It "Should not throw missing Solid property errors during menu startup" {
@@ -189,7 +192,7 @@ Describe "Main Entry Point" {
             Stop-Job $job -ErrorAction SilentlyContinue
             Remove-Job $job -Force -ErrorAction SilentlyContinue
 
-            $output | Should -Not -Match "property 'Solid' cannot be found|找不到属性.?Solid"
+            $output | Should -Not -Match $script:VisualDefaultsErrorPattern
         }
         
         It "Should list available commands in help" {

tests/Core.Tests.ps1

@@ -37,6 +37,41 @@ Describe "Base Module" {
         }
     }
 
+    Context "Visual Defaults Initialization" {
+        BeforeEach {
+            $script:OriginalColors = $script:Colors.Clone()
+            $script:OriginalIcons = $script:Icons.Clone()
+        }
+
+        AfterEach {
+            $script:Colors = $script:OriginalColors.Clone()
+            $script:Icons = $script:OriginalIcons.Clone()
+        }
+
+        It "Should initialize missing visual tables under strict mode" {
+            Remove-Variable -Name Colors -Scope Script -ErrorAction SilentlyContinue
+            Remove-Variable -Name Icons -Scope Script -ErrorAction SilentlyContinue
+
+            { Initialize-MoleVisualDefaults } | Should -Not -Throw
+            $script:Colors.Cyan | Should -Not -BeNullOrEmpty
+            $script:Colors.Green | Should -Not -BeNullOrEmpty
+            $script:Icons.Solid | Should -Not -BeNullOrEmpty
+            $script:Icons.Trash | Should -Not -BeNullOrEmpty
+        }
+
+        It "Should preserve existing values while filling missing defaults" {
+            $script:Colors = @{ Cyan = "custom-cyan" }
+            $script:Icons = @{ Solid = "*" }
+
+            Initialize-MoleVisualDefaults
+
+            $script:Colors.Cyan | Should -Be "custom-cyan"
+            $script:Colors.Green | Should -Not -BeNullOrEmpty
+            $script:Icons.Solid | Should -Be "*"
+            $script:Icons.Admin | Should -Not -BeNullOrEmpty
+        }
+    }
+
     Context "Test-IsAdmin" {
         It "Should return a boolean" {
             $result = Test-IsAdmin