improve: ralph loop prints no per-iteration status — users cannot tell which prompt is running or whether an iteration stalled

[ooloth]

Why

Without per-iteration progress output, users running a long ralph loop cannot distinguish a stalled iteration from a slow one, and cannot trace an error back to the specific prompt that caused it.

Current state

features/ralph/loop.py lines 143–154 output pprint(config) once at startup, then print bare === Iteration N === headers with no prompt name, model name, or indication of what is being sent or received.

Ideal state

• ralph prints a clear per-iteration status line that includes the prompt name, model, and iteration count
• The user knows the loop is progressing and can identify which iteration an error came from

Starting points

• features/ralph/loop.py — lines 143–154 contain the iteration loop and its current output statements

QA plan

1. Run a ralph loop with multiple prompts — Expect each iteration prints a status line identifying the prompt name, model, and iteration number before the response
2. Introduce a deliberate failure in one iteration — Expect the error output identifies which prompt and iteration number failed

Done when

Every ralph loop iteration prints a status line with at least the prompt name, model, and iteration count before sending the request.