columns/rows came straight from params with no cap. layout_lines loops
once per requested line and each push_unique scans the growing guide
vector, so a count like 200000000 (well inside u32) never returned -
blocking the app, CLI, MCP and the TCP control channel.
Reject counts above 1000 with an actionable BadParams naming the
offending parameter. Photoshop's own dialog caps at 32; 1000 is a
generous ceiling whose worst case finishes instantly, so legitimate
grids are untouched.
Adds regression tests: the issue repro (200M columns, and rows)
returns an actionable error immediately, and bounded layouts at the
cap still produce their guides.
Co-authored-by: Brandon Fenty <bfenty@users.noreply.github.com>
