Do not edit any file. Read svc/client.py and svc/config.py, then call done with an implementation plan (a numbered list of 6 to 10 steps) for adding client-side retries with exponential backoff and jitter to the HTTP client. The plan must name the exact files and functions to change, say how the retry limit and base delay become settings, say which failures are retried (for example HTTP 429 and 5xx, timeouts) and which are not, say how Retry-After is honoured, and say how it will be tested without a real network. Plan only, no code.
