Install telemetry.def so the config server can resolve it (#37246)

The ai.vespa.telemetry.telemetry config is produced by ContainerCluster
but telemetry.def was never installed to share/vespa/configdefinitions,
so a packaged config server's StaticConfigDefinitionRepo could not resolve
it. This made the config REST API config-traversal system test fail with
"Unable to find config definition for 'ai.vespa.telemetry.telemetry'".

Add the missing install_config_definition line (no vespa_generate_config:
telemetry.def has no C++ consumer, unlike open-telemetry.def).

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: onurkaracali

configdefinitions/src/vespa/CMakeLists.txt

@@ -36,6 +36,7 @@ vespa_generate_config(vespa_configdefinitions logforwarder.def)
 install_config_definition(logforwarder.def cloud.config.logforwarder.def)
 vespa_generate_config(vespa_configdefinitions open-telemetry.def)
 install_config_definition(open-telemetry.def cloud.config.open-telemetry.def)
+install_config_definition(telemetry.def ai.vespa.telemetry.telemetry.def)
 vespa_generate_config(vespa_configdefinitions messagetyperouteselectorpolicy.def)
 install_config_definition(messagetyperouteselectorpolicy.def vespa.config.content.messagetyperouteselectorpolicy.def)
 vespa_generate_config(vespa_configdefinitions model.def)