Commands: ids leave out an object listed with a group that holds it, as the selection does

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.

docs/mcp.md

@@ -274,7 +274,8 @@ currently describes them in prose, so MCP does not guess schemas or silently rem
 
 Coordinates are points in document space: y points down, the origin is the first artboard's top-left, and a new
 document is 612 × 792 (US Letter). New objects become the selection. Most commands act on the selection or on
-explicit `ids`.
+explicit `ids`. A command that leaves out an object selected inside a selected group also leaves it out when `ids`
+list it together with a group that holds it.
 
 Paint values (`fill`, `stroke`) accept `"#rrggbb"`, `"none"`, `[r,g,b]` (0..1), `{"c","m","y","k"}`, `{"gray"}`,
 or a full `paint.setFill` params object (`{"gradient": …}`, `{"swatch": "name"}`).