New app-level `copy` / `copy all` / `copy last` command (ADR-0041).
Delivery is OSC 52 *and* a best-effort native write (arboard), always
both — OSC 52 acceptance is undetectable, so a true fallback can't be
built. Payload is the panel's plain text exactly as rendered (tags,
✓/✗, box-drawing), drift-locked to render_output_line. arboard added
--no-default-features (X11-only; OSC 52 covers Wayland).
Amends ADR-0003's command registry; requirements V6.
55 tests covering create table, drop column, drop relationship
(endpoints + by-name), add relationship, rename/change column, and
all app-lifecycle commands. The drop-column and relationship tests
drove the §2.2 writes_table fix in the previous commit.
Documents one UX wrinkle as a flagged finding: partial entry words
(`qu`) classify as DefiniteErrorAt — same as unknown commands —
because the walker only engages on a complete entry word.
859 baseline -> 989 passing; 1 ignored (pre-existing doc-test).
Per docs/handoff/20260515-handoff-12.md §1. Systematic per-position
coverage of (state, hint, completion, parse_result) across canonical
schema shapes; submodule per command family. Insert Form A covers 23
cursor positions across serial-PK, text-PK, multi-table, and
every-Type schemas. Both bugs fixed in the previous commit were
surfaced by these tests.
Shared helpers under tests/typing_surface/mod.rs: 5 canonical schema
shapes, assess() helper, property-assertion shortcuts, and a snap!
macro that wraps insta with a stable per-cell suffix.
859 -> 885 tests passing; 1 ignored (pre-existing doc-test).