docs: update secondary action README examples

Author: bardonadam

README.md

@@ -323,15 +323,15 @@ activitysmith.live_activities.end_stream(
 
 ### Live Activity Action
 
-Live Activities can include a primary action button. `secondary_action` adds a secondary button for `alert`, `progress`, and `segmented_progress` Live Activities, using the same `open_url`, `shortcuts://`, and `webhook` payload shapes as `action`.
+Live Activities can include an action button.
 
 - `open_url`: open an HTTPS URL.
-- `open_url` with a `shortcuts://run-shortcut?name=...` URL: run a specific iPhone Shortcut, for example to open an app.
+- `open_url` with a `shortcuts://` URL: run an Apple Shortcut, for example to open an app.
 - `webhook`: trigger a backend GET/POST workflow.
 
 <p align="center">
   <img
-    src="https://cdn.activitysmith.com/features/live-activity-with-action.png?v=20260319-1"
+    src="https://cdn.activitysmith.com/features/metrics-live-activity-action.png"
     alt="Live Activity with action button"
     width="680"
   />
@@ -401,10 +401,53 @@ activitysmith.live_activities.stream(
             "requested_by": "activitysmith-python",
         },
     ),
+)
+```
+
+#### Secondary action
+
+<p align="center">
+  <img
+    src="https://cdn.activitysmith.com/features/live-activity-secondary-action.png"
+    alt="Alert Live Activity with primary and secondary action buttons"
+    width="680"
+  />
+</p>
+
+Use `secondary_action` when you want a second button beside the primary `action`.
+
+The secondary action button is supported for `alert`, `progress`, and `segmented_progress` Live Activities. Both buttons use the same `open_url`, `webhook`, and Apple Shortcut payload shapes.
+
+```python
+activitysmith.live_activities.stream(
+    "agent-approval",
+    content_state=content_state(
+        title="Approval Needed",
+        message="Should I send the follow-up email to Brightlane?",
+        type="alert",
+        color="green",
+        icon=alert_icon("sparkles", color="green"),
+        badge=alert_badge("Agent", color="green"),
+    ),
+    action=action(
+        title="Send",
+        type="webhook",
+        url="https://agent.example.com/live-activity/approve",
+        method="POST",
+        body={
+            "approval_id": "approval_01JY3J7Q9S0P8M1V5PZK7DR4M2",
+            "decision": "send",
+        },
+    ),
     secondary_action=action(
-        title="Open Runbook",
-        type="open_url",
-        url="https://ops.example.com/runbooks/search-reindex",
+        title="Deny",
+        type="webhook",
+        url="https://agent.example.com/live-activity/deny",
+        method="POST",
+        body={
+            "approval_id": "approval_01JY3J7Q9S0P8M1V5PZK7DR4M2",
+            "decision": "deny",
+        },
     ),
 )
 ```