polish(agents): activity-feed transcript UI pass

desktop/src-tauri/src/managed_agents/runtime.rs

@@ -1356,6 +1356,7 @@ pub fn build_managed_agent_summary(
         max_turn_duration_seconds: record.max_turn_duration_seconds,
         parallelism: record.parallelism,
         system_prompt: effective_prompt,
+        avatar_url: record.avatar_url.clone(),
         model: effective_model,
         mcp_toolsets: record.mcp_toolsets.clone(),
         env_vars: record.env_vars.clone(),

desktop/src-tauri/src/managed_agents/types.rs

@@ -224,6 +224,7 @@ pub struct ManagedAgentSummary {
     pub max_turn_duration_seconds: Option<u64>,
     pub parallelism: u32,
     pub system_prompt: Option<String>,
+    pub avatar_url: Option<String>,
     pub model: Option<String>,
     pub mcp_toolsets: Option<String>,
     #[serde(default, skip_serializing_if = "BTreeMap::is_empty")]