acp: Better telemetry IDs for ACP agents (#44544)

We were defining these in multiple places and also weren't leveraging
the ids the agents were already providing.

This should make sure we use them consistently and avoid issues in the
future.

Release Notes:

- N/A

crates/acp_thread/src/acp_thread.rs

@@ -1372,7 +1372,7 @@ impl AcpThread {
         let path_style = self.project.read(cx).path_style(cx);
         let id = update.tool_call_id.clone();
 
-        let agent = self.connection().telemetry_id();
+        let agent_telemetry_id = self.connection().telemetry_id();
         let session = self.session_id();
         if let ToolCallStatus::Completed | ToolCallStatus::Failed = status {
             let status = if matches!(status, ToolCallStatus::Completed) {
@@ -1380,7 +1380,12 @@ impl AcpThread {
             } else {
                 "failed"
             };
-            telemetry::event!("Agent Tool Call Completed", agent, session, status);
+            telemetry::event!(
+                "Agent Tool Call Completed",
+                agent_telemetry_id,
+                session,
+                status
+            );
         }
 
         if let Some(ix) = self.index_for_tool_call(&id) {
@@ -3556,8 +3561,8 @@ mod tests {
     }
 
     impl AgentConnection for FakeAgentConnection {
-        fn telemetry_id(&self) -> &'static str {
-            "fake"
+        fn telemetry_id(&self) -> SharedString {
+            "fake".into()
         }
 
         fn auth_methods(&self) -> &[acp::AuthMethod] {

crates/acp_thread/src/connection.rs

@@ -20,7 +20,7 @@ impl UserMessageId {
 }
 
 pub trait AgentConnection {
-    fn telemetry_id(&self) -> &'static str;
+    fn telemetry_id(&self) -> SharedString;
 
     fn new_thread(
         self: Rc<Self>,
@@ -322,8 +322,8 @@ mod test_support {
     }
 
     impl AgentConnection for StubAgentConnection {
-        fn telemetry_id(&self) -> &'static str {
-            "stub"
+        fn telemetry_id(&self) -> SharedString {
+            "stub".into()
         }
 
         fn auth_methods(&self) -> &[acp::AuthMethod] {