Currently, these Echo hook handlers are registered directly through extension-client.json without a hook handler, which prevents us from employing proper dependency injection.

AC:

• EchoSetupHookHandlers class is defined as a hook handler in extension-client.json
• All dependencies are injected to the hook handler through the service container

Notes:

• Followup to T256265: Migrate Client EchoSetupHookHandlers hook to extension JSON
• In the task above it was concluded that we cannot use the new system as Echo did not support it. A prerequisite to this task being completed is that Echo supports the new registration system.