Refactor Applications tab UI event handling

Consolidates the scattered event handlers for the Applications tab checkboxes into a single, centralized function and a shared event handler. This new approach manages the visibility of all dependent UI panels based on the state of the checkboxes.

This refactoring simplifies the codebase, eliminates redundant logic, and ensures a more consistent and predictable user interface state.

Additionally, this change fixes bugs where clearing list views for Winget results and drivers did not properly update their "select all" header checkboxes.

FFUDevelopment/FFUUI.Core/FFUUI.Core.psm1

@@ -189,6 +189,46 @@ function Get-USBDrives {
     }
 }
 
+# Function to manage the visibility of the application UI panels
+function Update-ApplicationPanelVisibility {
+    param(
+        [PSCustomObject]$State,
+        [string]$TriggeringControlName # Optional: to know which control initiated the change
+    )
+
+    $installAppsChecked = $State.Controls.chkInstallApps.IsChecked
+    
+    # If the main 'Install Apps' is unchecked, everything below it gets hidden and reset.
+    if ($TriggeringControlName -eq 'chkInstallApps' -and -not $installAppsChecked) {
+        $State.Controls.chkInstallWingetApps.IsChecked = $false
+        $State.Controls.chkBringYourOwnApps.IsChecked = $false
+        $State.Controls.chkDefineAppsScriptVariables.IsChecked = $false
+    }
+
+    $byoAppsChecked = $State.Controls.chkBringYourOwnApps.IsChecked
+    $wingetAppsChecked = $State.Controls.chkInstallWingetApps.IsChecked
+    $defineVarsChecked = $State.Controls.chkDefineAppsScriptVariables.IsChecked
+
+    # Visibility of primary sub-options
+    $subOptionVisibility = if ($installAppsChecked) { 'Visible' } else { 'Collapsed' }
+    $State.Controls.applicationPathPanel.Visibility = $subOptionVisibility
+    $State.Controls.appListJsonPathPanel.Visibility = $subOptionVisibility
+    $State.Controls.chkInstallWingetApps.Visibility = $subOptionVisibility
+    $State.Controls.chkBringYourOwnApps.Visibility = $subOptionVisibility
+    $State.Controls.chkDefineAppsScriptVariables.Visibility = $subOptionVisibility
+
+    # Visibility of panels dependent on sub-options
+    $State.Controls.byoApplicationPanel.Visibility = if ($installAppsChecked -and $byoAppsChecked) { 'Visible' } else { 'Collapsed' }
+    $State.Controls.wingetPanel.Visibility = if ($installAppsChecked -and $wingetAppsChecked) { 'Visible' } else { 'Collapsed' }
+    $State.Controls.appsScriptVariablesPanel.Visibility = if ($installAppsChecked -and $defineVarsChecked) { 'Visible' } else { 'Collapsed' }
+
+    # Special handling for wingetSearchPanel, which is shown by another button.
+    # We only collapse it if its parent becomes invisible.
+    if (-not ($installAppsChecked -and $wingetAppsChecked)) {
+        $State.Controls.wingetSearchPanel.Visibility = 'Collapsed'
+    }
+}
+
 # Function to manage the state of the main "Install Apps" checkbox based on selections in Updates/Office
 function Update-InstallAppsState {
     param([PSCustomObject]$State)