Added icons to visualize model capabilities to the provider dropdown menu (#829)

Co-authored-by: Thorsten Sommer <SommerEngineering@users.noreply.github.com>

app/MindWork AI Studio/Provider/AdditionalApiParametersParser.cs

@@ -0,0 +1,96 @@
+using System.Text.Json;
+
+namespace AIStudio.Provider;
+
+/// <summary>
+/// Parses the provider-specific JSON fragment stored in <see cref="IProvider.AdditionalJsonApiParameters"/>.
+/// </summary>
+/// <remarks>
+/// The provider settings UI stores only the body of a JSON object, such as
+/// <c>"temperature": 0.5</c>. This parser wraps that fragment in curly braces,
+/// parses it as JSON, and converts it to regular CLR dictionaries, lists, and
+/// primitive values so request builders and feature detectors can inspect it.
+/// </remarks>
+public static class AdditionalApiParametersParser
+{
+    /// <summary>
+    /// Try to parse an additional-API-parameters JSON fragment into a dictionary.
+    /// </summary>
+    /// <param name="additionalJsonApiParameters">The JSON object body without the surrounding curly braces.</param>
+    /// <param name="parameters">The parsed parameters if parsing succeeds; otherwise an empty dictionary.</param>
+    /// <param name="errorMessage">The JSON parsing error message if parsing fails; otherwise <see langword="null"/>.</param>
+    /// <returns><see langword="true"/> if the fragment is empty or valid JSON; otherwise <see langword="false"/>.</returns>
+    public static bool TryParse(string additionalJsonApiParameters, out IDictionary<string, object> parameters, out string? errorMessage)
+    {
+        parameters = new Dictionary<string, object>();
+        errorMessage = null;
+        if (string.IsNullOrWhiteSpace(additionalJsonApiParameters))
+            return true;
+
+        try
+        {
+            // The UI stores only the object body, so wrap it before parsing.
+            using var jsonDoc = JsonDocument.Parse($"{{{additionalJsonApiParameters}}}");
+            parameters = ConvertToDictionary(jsonDoc.RootElement);
+            return true;
+        }
+        catch (JsonException ex)
+        {
+            errorMessage = ex.Message;
+            return false;
+        }
+    }
+
+    /// <summary>
+    /// Remove keys from a parsed parameter dictionary using case-insensitive matching.
+    /// </summary>
+    /// <param name="parameters">The parsed parameter dictionary to mutate.</param>
+    /// <param name="keysToRemove">The parameter names that should be removed.</param>
+    /// <returns>The same dictionary instance after the matching keys were removed.</returns>
+    public static IDictionary<string, object> RemoveKeys(IDictionary<string, object> parameters, IEnumerable<string> keysToRemove)
+    {
+        var removeSet = new HashSet<string>(keysToRemove, StringComparer.OrdinalIgnoreCase);
+        if (removeSet.Count is 0)
+            return parameters;
+
+        foreach (var key in parameters.Keys.ToList())
+            if (removeSet.Contains(key))
+                parameters.Remove(key);
+
+        return parameters;
+    }
+
+    /// <summary>
+    /// Convert a JSON object element into a dictionary of recursively converted CLR values.
+    /// </summary>
+    /// <param name="element">The JSON object element to convert.</param>
+    /// <returns>A dictionary containing all JSON object properties.</returns>
+    private static IDictionary<string, object> ConvertToDictionary(JsonElement element)
+    {
+        return element.EnumerateObject()
+            .ToDictionary<JsonProperty, string, object>(
+                p => p.Name,
+                p => ConvertJsonValue(p.Value) ?? string.Empty
+            );
+    }
+
+    /// <summary>
+    /// Convert a JSON value to the closest CLR representation used by provider request objects.
+    /// </summary>
+    /// <param name="element">The JSON element to convert.</param>
+    /// <returns>A string, number, boolean, dictionary, list, or empty string for unsupported/null values.</returns>
+    private static object? ConvertJsonValue(JsonElement element) => element.ValueKind switch
+    {
+        JsonValueKind.String => element.GetString(),
+        JsonValueKind.Number => element.TryGetInt32(out var i) ? i :
+            element.TryGetInt64(out var l) ? l :
+            element.TryGetDouble(out var d) ? d :
+            element.GetDecimal(),
+        JsonValueKind.True or JsonValueKind.False => element.GetBoolean(),
+        JsonValueKind.Null => string.Empty,
+        JsonValueKind.Object => ConvertToDictionary(element),
+        JsonValueKind.Array => element.EnumerateArray().Select(ConvertJsonValue).ToList(),
+
+        _ => string.Empty,
+    };
+}