Restore “Log in with Google” on canary

The “Log in with Google” button is now available on the canary environment. The button only appears when both Google OAuth client ID and secret environment variables are present, and the canary secrets blob was missing the Google OAuth block, so canary alone hid the button while staging and production kept it. This chart change wires Google OAuth credentials through External Secrets Operator from 1Password, the same pattern already used for GitHub App credentials, so managed environments get the button back and the migration of OAuth secrets out of the encrypted secrets blob continues.