install report_error isolation

Installer report_error() telemetry must be fire-and-forget and unable to fail, block, delay, interrupt, or change installation. Run it in a background subshell with set +e, silent short-timeout curl, a public write-only Sentry envelope DSN, no PII, and SENTRY_CLI_NO_TELEMETRY=1 opt-out. Never wait for the telemetry subprocess in die(); preserving the installer’s original output, failure, and exit code is more important than delivery.