fix: chunk upload race — always return the completed response with filepath; add campaign name to setup wizard

docker-compose.example.yml

@@ -20,6 +20,9 @@ services:
       # Set to "true" after onboarding completes.
       NAT20_ONBOARDING_COMPLETED: "false"
 
+      # Campaign name is set during the setup wizard (step 2).
+      # You can also rename it later in Settings → Campaigns.
+
       # ── Transcription ─────────────────────────────────────
       NAT20_WHISPER_MODEL: medium
       NAT20_WHISPER_COMPUTE_TYPE: int8