FLAC normalization renames the backend's WAV destination. The next
request then reuses that apparently vacant path and replaces the first
recording when normalization runs again.
Give each request a UUID filename, and test that successive FLAC outputs
retain distinct paths and their original bytes.
Addresses the overwrite report in #12633. Reference-audio input remains
outside this fix.
Assisted-by: Codex:gpt-6
Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Co-authored-by: localai-org-maint-bot <306269227+localai-org-maint-bot@users.noreply.github.com>