feat: align browser callback runtime and export flows

Consolidate the browser task runtime around the callback path, add safer artifact opening for Zhihu exports, and cover the new service/browser flows with focused tests and supporting docs.

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

src/agent/task_runner.rs

@@ -40,13 +40,13 @@ impl AgentRuntimeContext {
                         "missing value for --config-path".to_string(),
                     ));
                 };
-                config_path = Some(PathBuf::from(value));
+                config_path = Some(resolve_process_path(PathBuf::from(value)));
                 continue;
             }
 
             let arg_string = arg.to_string_lossy();
             if let Some(value) = arg_string.strip_prefix("--config-path=") {
-                config_path = Some(PathBuf::from(value));
+                config_path = Some(resolve_process_path(PathBuf::from(value)));
             }
         }
 
@@ -81,6 +81,37 @@ fn default_workspace_root() -> PathBuf {
     std::env::current_dir().unwrap_or_else(|_| PathBuf::from("."))
 }
 
+fn resolve_process_path(path: PathBuf) -> PathBuf {
+    if path.is_absolute() {
+        path
+    } else {
+        default_workspace_root().join(path)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn from_process_args_resolves_relative_config_path_against_current_dir() {
+        let current_dir = std::env::current_dir().unwrap();
+        let context = AgentRuntimeContext::from_process_args([
+            OsString::from("sg_claw"),
+            OsString::from("--config-path"),
+            OsString::from("../tmp/sgclaw_config.json"),
+        ])
+        .unwrap();
+
+        assert_eq!(
+            context.config_path,
+            Some(current_dir.join("../tmp/sgclaw_config.json"))
+        );
+        assert_eq!(context.workspace_root, current_dir.join("../tmp"));
+        assert!(context.workspace_root.is_absolute());
+    }
+}
+
 #[derive(Debug, Clone, Default, PartialEq, Eq)]
 pub struct SubmitTaskRequest {
     pub instruction: String,