README: the API key placeholder uses a prefix real keys do not have #107

Summary

The README tells you to set your key like this, in two places:

export CALLE_API_KEY="calle_live_key"

Lines 199 and 261.

Real keys do not look like that. The authentication guide says production keys carry the iams_live_ prefix, and the dashboard hands out keys in that shape.

It is small, but it lands at an unhelpful moment. Someone copies that line, pastes their real key over it, and the only reference point they have for what a key should look like now disagrees with the key in their hand. If the next request fails for an unrelated reason, the prefix is a plausible thing to start doubting.

The docs already use iams_live_example as their placeholder, which is unmistakably a placeholder and the right shape.

Where

README.md, lines 199 and 261.

Suggested fix

Match the docs:

export CALLE_API_KEY="iams_live_example"

Worth a grep for calle_live across the repo while you are in there, in case it survives anywhere else.