Emit analytics for remote plugin installs (#20267)

## Summary

- emit `codex_plugin_installed` after a remote plugin install succeeds
- keep local installs unchanged, but let remote installs override the
analytics `plugin_id` with the backend remote plugin id
(`plugins~Plugin_...`)
- preserve the local/display identity in `plugin_name` and
`marketplace_name`, plus capability metadata from the installed bundle
- add regression coverage for local install analytics, remote install
analytics, and analytics id override serialization

## Testing

- `just fmt`
- `cargo test -p codex-analytics`
- `cargo test -p codex-app-server`

codex-rs/app-server/src/codex_message_processor/plugins.rs

@@ -505,7 +505,7 @@ impl CodexMessageProcessor {
     async fn remote_plugin_install_response(
         &self,
         remote_marketplace_name: String,
-        plugin_name: String,
+        remote_plugin_id: String,
     ) -> Result<PluginInstallResponse, JSONRPCErrorError> {
         let config = self.load_latest_config(/*fallback_cwd*/ None).await?;
         if !config.features.enabled(Feature::Plugins)
@@ -513,8 +513,10 @@ impl CodexMessageProcessor {
         {
             return Err(invalid_request("remote plugin install is not enabled"));
         }
-        if plugin_name.is_empty() || !is_valid_remote_plugin_id(&plugin_name) {
-            return Err(invalid_request("invalid remote plugin id"));
+        if remote_plugin_id.is_empty() || !is_valid_remote_plugin_id(&remote_plugin_id) {
+            return Err(invalid_request(
+                "invalid remote plugin id: only ASCII letters, digits, `_`, `-`, and `~` are allowed",
+            ));
         }
 
         let auth = self.auth_manager.auth().await;
@@ -526,7 +528,7 @@ impl CodexMessageProcessor {
                 &remote_plugin_service_config,
                 auth.as_ref(),
                 &remote_marketplace_name,
-                &plugin_name,
+                &remote_plugin_id,
             )
             .await
             .map_err(|err| {
@@ -537,7 +539,7 @@ impl CodexMessageProcessor {
             })?;
         if remote_detail.summary.install_policy == PluginInstallPolicy::NotAvailable {
             return Err(invalid_request(format!(
-                "remote plugin {plugin_name} is not available for install"
+                "remote plugin {remote_plugin_id} is not available for install"
             )));
         }
         let actual_remote_marketplace_name = remote_detail.marketplace_name.clone();
@@ -550,7 +552,7 @@ impl CodexMessageProcessor {
                 &remote_detail.summary.name,
             );
         let validated_bundle = codex_core_plugins::remote_bundle::validate_remote_plugin_bundle(
-            &plugin_name,
+            &remote_plugin_id,
             &actual_remote_marketplace_name,
             &remote_detail.summary.name,
             remote_detail.release_version.as_deref(),
@@ -572,7 +574,7 @@ impl CodexMessageProcessor {
             &remote_plugin_service_config,
             auth.as_ref(),
             &actual_remote_marketplace_name,
-            &plugin_name,
+            &remote_plugin_id,
         )
         .await
         .map_err(|err| remote_plugin_catalog_error_to_jsonrpc(err, "install remote plugin"))?;
@@ -585,6 +587,12 @@ impl CodexMessageProcessor {
                 Some(self.effective_plugins_changed_callback(config.clone())),
             );
 
+        let mut plugin_metadata =
+            plugin_telemetry_metadata_from_root(&result.plugin_id, &result.installed_path).await;
+        plugin_metadata.remote_plugin_id = Some(remote_plugin_id);
+        self.analytics_events_client
+            .track_plugin_installed(plugin_metadata);
+
         let plugin_mcp_servers = load_plugin_mcp_servers(result.installed_path.as_path()).await;
         if !plugin_mcp_servers.is_empty() {
             self.start_plugin_mcp_oauth_logins(&config, plugin_mcp_servers)