A large RPC result was fully split into lines and copied before being
handed to the console, even though only the last few lines could survive
the model's line cap.
- The formatter now takes a line cap and keeps only the last N lines,
located by a backward newline scan, so a huge result is never fully
split or copied. JSON classification still keys off the first
character of the whole result.
- It works over a string view and moves line text through, and fold
spans are computed over the formatted lines directly instead of a
separate vector of copies.
- getline semantics are preserved: a trailing newline adds no empty
line and an empty result yields no lines.
Tests: getline parity for empty, trailing-newline and blank-line inputs,
the backward tail cap, and JSON classification and fold spans over a
capped result.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
DanSandClaude Opus 4.8
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