Every lookup by id walked the whole tree, and the edit path did one per selected id, so editing
a selection of n objects cost O(n²). Measured with the new `perf --deep` rows at 25,000 paths:
- Select All: 458 → 3.5 ms
- nudge the selection: 3,517 → 34 ms
- drag it with the Selection tool, per pointer move: 3,413 → 35 ms
- undo / redo: 407 → 3.1 ms
- vectorcraft_doc: Document::index_paths (every id's index path, in one walk; the first in tree
order for a duplicated id, as index_path), node_at, node_mut_at (copy-on-write, as node_mut)
and ancestry_at.
- apply_transform, roots_of, transform_patterns, doc_sane, Selection::prune and
Document::paint_order look their ids up with one walk instead of one each.
- Selection::set dedups with a hash set instead of Vec::contains per id.
- vectorcraft-cli perf --deep: tracked rows for editing a whole selection (select, nudge, drag,
undo, redo), live effects, every Pathfinder operation, typing in a long story, and memory.
tests_lookups checks the batched lookups against the one-id ones on nested trees with missing and
duplicated ids; storing the last duplicate instead of the first fails it. The doc and engine
suites (2,000 tests) pass unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VmMmc1J8XeNLxhRihWv9cc
4b260c364d