patch against ggml-org/llama.cpp#21174 to add multimodal tool call responses

pr-21174-multimodal-tool.patch

diff --git a/tools/server/server-chat.cpp b/tools/server/server-chat.cpp
index 8ef7766fd..1626f70db 100644
--- a/tools/server/server-chat.cpp
+++ b/tools/server/server-chat.cpp
@@ -31,7 +31,7 @@ json server_chat_convert_responses_to_chatcmpl(const json & response_body) {
         throw std::invalid_argument("llama.cpp does not support 'previous_response_id'.");
     }
 
-    const json input_value = response_body.at("input");
+    const json & input_value = response_body.at("input");
     json chatcmpl_body = response_body;
     chatcmpl_body.erase("input");
     std::vector<json> chatcmpl_messages;
@@ -276,16 +276,47 @@ json server_chat_convert_responses_to_chatcmpl(const json & response_body) {
                         {"tool_call_id", item.at("call_id")},
                     });
                 } else {
-                    json chatcmpl_outputs = item.at("output");
-                    for (json & chatcmpl_output : chatcmpl_outputs) {
-                        if (!chatcmpl_output.contains("type") || chatcmpl_output.at("type") != "input_text") {
-                            SRV_DBG("responses compat: item_type='%s', action='treat_tool_output_as_text'\n",
-                                    json_value(chatcmpl_output, "type", std::string("missing")).c_str());
+                    // Walk output parts. Translate Responses-API content types
+                    // into chat-completions content types in place; the
+                    // downstream `oaicompat_chat_params_parse` then fetches
+                    // any `image_url` parts via `handle_media()` and replaces
+                    // them with the model's media marker, which the chat
+                    // template renders normally regardless of role.
+                    std::vector<json> tool_content;
+                    const std::string tool_role = "tool";
+                    for (const json & output_part : item.at("output")) {
+                        const std::string type = json_value(output_part, "type", std::string());
+                        if (type == "input_text" || type == "output_text" || type == "text") {
+                            if (!exists_and_is_string(output_part, "text")) {
+                                responses_append_recovery_text(tool_content, tool_role, type, type + " item missing text");
+                                continue;
+                            }
+                            tool_content.push_back({
+                                {"text", output_part.at("text")},
+                                {"type", "text"},
+                            });
+                        } else if (type == "input_image") {
+                            if (!output_part.contains("image_url")) {
+                                responses_append_recovery_text(tool_content, tool_role, type, "input_image item missing image_url");
+                                continue;
+                            }
+                            tool_content.push_back({
+                                {"image_url", json {
+                                    {"url", output_part.at("image_url")}
+                                }},
+                                {"type", "image_url"},
+                            });
+                        } else {
+                            const std::string item_type = type.empty() ? std::string("unknown") : type;
+                            responses_append_recovery_text(
+                                    tool_content,
+                                    tool_role,
+                                    item_type,
+                                    "unsupported tool_output content type " + item_type);
                         }
-                        chatcmpl_output["type"] = "text";
                     }
                     chatcmpl_messages.push_back(json {
-                        {"content",      chatcmpl_outputs},
+                        {"content",      tool_content},
                         {"role",         "tool"},
                         {"tool_call_id", item.at("call_id")},
                     });