fix: resolve wasm broadcast merge conflicts with staging (#395) (#1460)

* channels/wasm: implement telegram broadcast path for message tool

* channels/wasm: tighten telegram broadcast contract and tests

* fix: resolve merge conflicts with staging for wasm broadcast

- Remove duplicate broadcast() impls from WasmChannel and SharedWasmChannel
  (staging already has the generic call_on_broadcast path)
- Remove obsolete telegram-specific test helpers and tests that tested
  the old telegram-only broadcast logic
- Add test_broadcast_delegates_to_call_on_broadcast for the generic path
- Fix missing fallback_deliverable field in job_monitor test SseEvents

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

---------

Co-authored-by: davidpty <[email protected]>
Co-authored-by: firat.sertgoz <[email protected]>
Co-authored-by: Claude Opus 4.6 (1M context) <[email protected]>

src/agent/job_monitor.rs

@@ -421,6 +421,7 @@ mod tests {
                     job_id: job_id.to_string(),
                     status: "completed".to_string(),
                     session_id: None,
+                    fallback_deliverable: None,
                 },
             ))
             .unwrap();
@@ -468,6 +469,7 @@ mod tests {
                     job_id: job_id.to_string(),
                     status: "failed".to_string(),
                     session_id: None,
+                    fallback_deliverable: None,
                 },
             ))
             .unwrap();
@@ -506,6 +508,7 @@ mod tests {
                     job_id: job_id.to_string(),
                     status: "completed".to_string(),
                     session_id: None,
+                    fallback_deliverable: None,
                 },
             ))
             .unwrap();

src/channels/wasm/wrapper.rs

@@ -3314,6 +3314,7 @@ mod tests {
     use std::sync::Arc;
 
     use crate::channels::Channel;
+    use crate::channels::OutgoingResponse;
     use crate::channels::wasm::capabilities::ChannelCapabilities;
     use crate::channels::wasm::runtime::{
         PreparedChannelModule, WasmChannelRuntime, WasmChannelRuntimeConfig,
@@ -3401,6 +3402,16 @@ mod tests {
         assert!(channel.health_check().await.is_err());
     }
 
+    #[tokio::test]
+    async fn test_broadcast_delegates_to_call_on_broadcast() {
+        let channel = create_test_channel();
+        // With `component: None`, call_on_broadcast short-circuits to Ok(()).
+        let result = channel
+            .broadcast("146032821", OutgoingResponse::text("hello"))
+            .await;
+        assert!(result.is_ok());
+    }
+
     #[tokio::test]
     async fn test_execute_poll_no_wasm_returns_empty() {
         // When there's no WASM module (None component), execute_poll