Commands that read the selection through edit::selected_roots leave
out an object whose group is also selected (edit::roots_of). Fourteen
places that read `ids` kept an object listed together with its group.
Given ids that list an object and a group that holds it, Make Repeat
failed with "no such object", New Symbol failed or stored the object
twice in the symbol, and object.transform moved it twice (20 pt for a
10 pt move).
These places now pass explicit ids through edit::outermost, which
drops an id whose ancestor is also listed, with the filter that
roots_of runs on the selection (now edit::without_inner). Nothing else
is dropped or replaced: unlike roots_of, it keeps layers and
compound-path members. A list without nesting gives the same result as
before. Commands that take both ids and the selection as listed, such
as paint.setFill without item, are unchanged.
Docs: docs/mcp.md, docs/target-app-parity.md.
Commands whose description takes `ids` (operate on these objects;
default: the selection) failed with "nothing selected" when objects
were given but none was selected: execute checked their `enabled`
predicate against the selection, with an exception for edit.clear only.
Of the 220 commands mentioning ids, 48 were refused so; their run
already used the ids. execute now evaluates `enabled` with the given
ids selected and puts the selection back, so each predicate keeps its
meaning (Make with Top Object still needs two objects).
Fixes#1575
dotCooCoo