Update body_snapshot docstring for clarity

Clarify behavior of body_snapshot method for LoggableResponseBody.

Author: Benflow3

packages/dexpace-sdk-core/src/dexpace/sdk/core/errors/http.py

@@ -112,9 +112,9 @@ def _status_is_retryable(self) -> bool:
     def body_snapshot(self, max_bytes: int | None = None) -> bytes:
         """Preview the error response body without consuming it.
 
-        Safe to call from logging and post-mortem paths: it never drains a
-        single-use stream. Bytes are only returned when the body has already
-        been captured for repeatable reads (a ``LoggableResponseBody``); for
+        For a LoggableResponseBody, the snapshot drains and caches the inner
+        body on the first access (this initial read is synchronous and
+        may incur I/O, but subsequent reads are repeatable and fast); for
         any other body — or when no response/body is present — an empty
         ``bytes`` is returned rather than destroying the payload.