refactor: instance are in unrecoverable state instead of error

To avoid confusion between error from a call or network.
Instance has an Unrecoverable state instead of Error.

app/http/routes/models/blocking_request.go

@@ -0,0 +1,9 @@
+package models
+
+import "time"
+
+type BlockingRequest struct {
+	Names           []string
+	SessionDuration time.Duration
+	Timeout         time.Duration
+}