fix(kotlin-host): pass tool arguments to callTool instead of empty map

The callTool method was being called with emptyMap() for arguments,
ignoring the parsed input. This caused tools to receive no data.

Fixed both:
- callTool() in the direct tool call flow
- forwardToolCall() for WebView-initiated tool calls

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: ochafik

examples/basic-host-kotlin/src/main/kotlin/com/example/mcpappshost/McpHostViewModel.kt

@@ -222,8 +222,27 @@ class McpHostViewModel : ViewModel() {
                     null
                 }
 
+                // Convert JsonObject to Map<String, Any?> for SDK
+                val argsMap = inputArgs?.let { args ->
+                    args.mapValues { (_, v) ->
+                        when (v) {
+                            is JsonPrimitive -> when {
+                                v.isString -> v.content
+                                v.booleanOrNull != null -> v.boolean
+                                v.intOrNull != null -> v.int
+                                v.longOrNull != null -> v.long
+                                v.doubleOrNull != null -> v.double
+                                else -> v.content
+                            }
+                            else -> v.toString()
+                        }
+                    }
+                } ?: emptyMap()
+
+                Log.i(TAG, "Calling tool ${tool.name} with args: $argsMap")
+
                 // Call the tool (name, arguments, meta, options)
-                val callResult = client.callTool(tool.name, emptyMap(), emptyMap())
+                val callResult = client.callTool(tool.name, argsMap, emptyMap())
 
                 // Check for UI resource
                 if (tool.uiResourceUri != null) {
@@ -340,7 +359,7 @@ class McpHostViewModel : ViewModel() {
 
         Log.i(TAG, "Forwarding tool call: $name with args: $arguments")
 
-        val callResult = client.callTool(name, emptyMap(), emptyMap())
+        val callResult = client.callTool(name, arguments ?: emptyMap(), emptyMap())
 
         // Format result as JSON for the App
         val resultJson = json.encodeToString(