Fix: Prevent git popup when Source Control is disabled (#2138)

Fixed issue where CodeEdit would show "The 'git' command requires the
command line developer tools. Would you like to install the tools now?"
popup on every app launch, even when Source Control was completely
disabled in Settings.

Issue Analysis:
- WorkspaceView.swift was unconditionally calling git operations
  (refreshRemotes and refreshStashEntries) on every workspace launch
- These git commands triggered macOS to show the Command Line Developer
  Tools installation popup if git wasn't installed
- The operations ran regardless of the sourceControlIsEnabled setting

Solution:
- Added guard statement to check sourceControlIsEnabled before running
  git operations in the .task block
- Now git commands only execute when Source Control is enabled in Settings
- Also updated onChange syntax to modern two-parameter form

Result:
- Users who disable Source Control no longer see the git tools popup
- Git operations still work normally when Source Control is enabled
- Popup behavior now respects user preferences as expected

Fixes #2138

Author: vksvicky

CodeEdit/WorkspaceView.swift

@@ -85,6 +85,9 @@ struct WorkspaceView: View {
                     // MARK: - Source Control
 
                     .task {
+                        // Only refresh git data if source control is enabled
+                        guard sourceControlIsEnabled else { return }
+                        
                         do {
                             try await sourceControlManager.refreshRemotes()
                             try await sourceControlManager.refreshStashEntries()
@@ -95,7 +98,7 @@ struct WorkspaceView: View {
                             )
                         }
                     }
-                    .onChange(of: sourceControlIsEnabled) { newValue in
+                    .onChange(of: sourceControlIsEnabled) { _, newValue in
                         if newValue {
                             Task {
                                 await sourceControlManager.refreshCurrentBranch()