Update documentation relating to the public packages and http_upload API

docs/operations.md

@@ -148,18 +148,7 @@ curl -X POST http://127.0.0.1:8080/upload \
   --data-binary @bundle.tar.gz
 ```
 
-Go producer applications can use `pkg/upload` instead of constructing archives and HTTP requests directly. The package sends `Idempotency-Key` on every upload, derives `/upload` from the configured endpoint, and reuses the same key and replayable request body for safe retries:
-
-```go
-client, err := upload.NewClient(upload.ClientOptions{
-	Endpoint: "http://127.0.0.1:8080",
-	Token:    token,
-})
-result, err := client.UploadBundle(ctx, upload.UploadBundleOptions{
-	Root:           "examples/source-bundle",
-	IdempotencyKey: "producer.run.20260604T120000Z",
-})
-```
+Go producer applications can use `pkg/upload` instead of constructing archives and HTTP requests directly. See [Upstream Producer Integration](consumers/api.md) for the copyable producer implementation guide.
 
 The maintained example client uses the local upload server and reads the token from `DISTRIBUTOR_EXAMPLE_UPLOAD_TOKEN`. It generates an idempotency key by default; set `DISTRIBUTOR_EXAMPLE_UPLOAD_IDEMPOTENCY_KEY` when a retry must be stable across separate process runs.