Fix advanced paste migration issue (#43524)

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fix/what does it change/how was it tested (even manually, if necessary)?
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## Summary of the Pull Request
This pull request refactors how legacy AI enablement settings are
migrated and simplifies the handling of legacy properties in the
settings UI. The main improvements are in the migration logic and the
removal of legacy extension data handling.


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## PR Checklist

- [ ] Closes: #xxx
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
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pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
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pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

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## Detailed Description of the Pull Request / Additional comments

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Signed-off-by: Shawn Yuan <shuai.yuan.zju@gmail.com>

src/modules/AdvancedPaste/AdvancedPaste/Helpers/UserSettings.cs

@@ -213,10 +213,11 @@ namespace AdvancedPaste.Settings
                 RemoveLegacyOpenAICredential();
             }
 
+            bool shouldEnableAI = legacyCredential is not null;
             bool enabledUpdated = false;
-            if (!properties.IsAIEnabled && legacyCredential is not null)
+            if (properties.IsAIEnabled != shouldEnableAI)
             {
-                properties.IsAIEnabled = true;
+                properties.IsAIEnabled = shouldEnableAI;
                 enabledUpdated = true;
             }
 

src/settings-ui/Settings.UI.Library/AdvancedPasteProperties.cs

@@ -34,52 +34,6 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         [JsonConverter(typeof(BoolPropertyJsonConverter))]
         public bool IsAIEnabled { get; set; }
 
-        [JsonExtensionData]
-        public Dictionary<string, JsonElement> ExtensionData
-        {
-            get => _extensionData;
-            set
-            {
-                _extensionData = value;
-
-                if (_extensionData != null && _extensionData.TryGetValue("IsOpenAIEnabled", out var legacyElement) && legacyElement.ValueKind == JsonValueKind.Object && legacyElement.TryGetProperty("value", out var valueElement))
-                {
-                    IsAIEnabled = valueElement.ValueKind switch
-                    {
-                        JsonValueKind.True => true,
-                        JsonValueKind.False => false,
-                        _ => IsAIEnabled,
-                    };
-
-                    _extensionData.Remove("IsOpenAIEnabled");
-                }
-
-                if (_extensionData != null && _extensionData.TryGetValue("IsAdvancedAIEnabled", out var legacyAdvancedElement))
-                {
-                    bool? legacyValue = legacyAdvancedElement.ValueKind switch
-                    {
-                        JsonValueKind.True => true,
-                        JsonValueKind.False => false,
-                        JsonValueKind.Object when legacyAdvancedElement.TryGetProperty("value", out var advancedValueElement) => advancedValueElement.ValueKind switch
-                        {
-                            JsonValueKind.True => true,
-                            JsonValueKind.False => false,
-                            _ => null,
-                        },
-                        _ => null,
-                    };
-
-                    if (legacyValue.HasValue)
-                    {
-                        LegacyAdvancedAIEnabled = legacyValue.Value;
-                    }
-
-                    _extensionData.Remove("IsAdvancedAIEnabled");
-                }
-            }
-        }
-
-        private Dictionary<string, JsonElement> _extensionData;
         private bool? _legacyAdvancedAIEnabled;
 
         [JsonPropertyName("IsAdvancedAIEnabled")]

src/settings-ui/Settings.UI/ViewModels/AdvancedPasteViewModel.cs

@@ -233,10 +233,11 @@ namespace Microsoft.PowerToys.Settings.UI.ViewModels
                 RemoveLegacyOpenAICredential();
             }
 
+            bool shouldEnableAI = legacyCredential is not null;
             bool enabledChanged = false;
-            if (!properties.IsAIEnabled && legacyCredential is not null)
+            if (properties.IsAIEnabled != shouldEnableAI)
             {
-                properties.IsAIEnabled = true;
+                properties.IsAIEnabled = shouldEnableAI;
                 enabledChanged = true;
             }