An attachment over the side or area caps whose re-encode did not shrink
the byte count was returned unchanged at its original dimensions, so the
provider still received an over-cap image. The byte-saving short-circuit
now applies only within the caps; a resize that would fall under the
vision minimums keeps the original on the existing fallback path.
Ported from upstream 1.0.13 (grok-build session/image_normalize.rs).
Claude-Session: https://claude.ai/code/session_01RUqV8HVGXcAETyYbZ2tPQ4
雷电芽衣
d8609267a1