Because:
- The events ping with event metric type replaced accounts-events in 2024 and every known consumer has moved to it.
- Each frontend event cost two pings and each backend event two log entries.
This commit:
- Drops the accounts-events ping and its event.* string metrics from the Glean YAML definitions.
- Removes the ping submit and legacy record calls from fxa-settings, content-server and auth-server, and regenerates the Glean modules.
- Keeps the pings and compat YAML files as schema-only stubs because probe-scraper still fetches them by path.
- Reworks the Glean unit tests to assert on the event metrics instead of the removed string metrics.
Closes: FXA-10679
Closes: FXA-10681