Added specific error handling for images exceeding the 2000px dimension limit in many-image requests. The error message now provides actionable guidance:
In interactive mode: "Run /compact to remove old images from context, or start a new session"
In non-interactive mode: "Start a new session with fewer images"
Evidence
Image dimension handling (search for "image dimensions exceed")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
