Add problem statement
MODIFY
docs/interop-design/interop-design.md
docs/interop-design/interop-design.md
-# Interoperability of bytecode instrumentation with user/library instrumentation
+# Interoperability design
+
+## Problem statement
+
+These two things must seamlessly interoperate:
+
+* Instrumentation provided by the Java agent
+* Instrumentation provided by the user app, using any 1.0+ version of the OpenTelemetry API
## Design

Add problem statement (#1639)