feat: add config-owned direct submit runtime

Keep browser-attached workflows on the configured direct-skill path and align the Zhihu export/browser regression contracts with the current ws merge state.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/agent/task_runner.rs

@@ -198,6 +198,37 @@ pub fn run_submit_task<T: Transport + 'static>(
                     settings.runtime_profile, settings.skills_prompt_mode
                 ),
             });
+            if settings.direct_submit_skill.is_some() {
+                match crate::compat::direct_skill_runtime::execute_direct_submit_skill(
+                    browser_tool.clone(),
+                    &instruction,
+                    &task_context,
+                    &context.workspace_root,
+                    &settings,
+                ) {
+                    Ok(outcome) => {
+                        let _ = send_mode_log(sink, "direct_skill_primary");
+                        return sink.send(&AgentMessage::TaskComplete {
+                            success: outcome.success,
+                            summary: outcome.summary,
+                        });
+                    }
+                    Err(PipeError::Protocol(message))
+                        if message.contains("must use skill.tool format") =>
+                    {
+                        return sink.send(&AgentMessage::TaskComplete {
+                            success: false,
+                            summary: message,
+                        });
+                    }
+                    Err(err) => {
+                        return sink.send(&AgentMessage::TaskComplete {
+                            success: false,
+                            summary: err.to_string(),
+                        });
+                    }
+                }
+            }
             if RuntimeEngine::new(settings.runtime_profile).browser_surface_enabled()
                 && crate::compat::orchestration::should_use_primary_orchestration(
                     &instruction,