Add GLM 5.3 Flash support

src/agent.rs

@@ -3612,7 +3612,7 @@ pub(crate) fn parse_tool_calls(
     model: ModelChoice,
     text: &str,
 ) -> Result<(String, Vec<ToolCall>), String> {
-    let (content, calls) = if model == ModelChoice::Glm52 {
+    let (content, calls) = if model.is_glm() {
         parse_glm_calls(text)?
     } else {
         crate::dsml::parse_tool_calls(text)?
@@ -3643,7 +3643,7 @@ fn system_prompt_with_tools(
     ralph_child: bool,
 ) -> String {
     let schemas = tool_schemas(dev_brain, ralph_child);
-    let tools = if model == ModelChoice::Glm52 {
+    let tools = if model.is_glm() {
         format!(
             "You are a coding agent running in a local workspace. Use tools for local file and system work. Avoid printing large file contents or code blocks as answers; edit files with tools, then summarize briefly.\n\n# Tools\n\n<tools>\n{schemas}\n</tools>\n\nFor a function call, output exactly: <tool_call>function-name<arg_key>key</arg_key><arg_value>value</arg_value></tool_call>\nTool calls are not allowed inside <think></think>. Pass numbers and booleans as JSON primitives, not quoted strings. When a tool fails validation or execution, use its code, field, expected, and received feedback to correct the next call. Preserve the current system configuration unless the user explicitly asks otherwise."
         )