Brushes: Shift-click and Ctrl/Cmd-click select several brushes, and Delete Brush deletes them

A Shift-click or Ctrl/Cmd-click on a brush in the Brushes panel used to
apply the brush, as a plain click does. It now selects brushes without
applying one. Shift-click adds the brushes from the last brush clicked
without Shift (else the highlighted brush) to the clicked one, in the
order the panel shows them. Ctrl/Cmd-click adds the clicked brush to the
highlighted brushes or removes it. The panel highlights the selected
brushes, and the bottom bar's Delete Brush and the panel menu's
Duplicate Brush and Delete Brush act on all of them. A plain click
works as before and ends the multi-selection, and so does selecting
other art, another document or another current brush.

brush.delete and brush.duplicate also take {names: [name...]}. Each
call is one undo step, and an unknown name fails before anything
changes. brush.duplicate answers {names} for a names list.

Docs: docs/mcp.md, docs/target-app-parity.md.

docs/mcp.md

@@ -1098,7 +1098,8 @@ already walks Image Trace. Short agent entry points:
   `symbol.place {name?, x?, y?}`, `symbol.breakLink {ids?}`, `symbol.replace`, `symbol.edit`, `symbol.duplicate`,
   `symbol.selectInstances {name}`.
 - Brushes: `brush.list`, `brush.get {name}`, `brush.apply {name, ids?}`, `brush.new {type, name?, params?, ids?}`,
-  `brush.setCurrent {name}`, `brush.options {name, params?}`, `brush.freehand`, `object.expandBrush {ids?}`.
+  `brush.setCurrent {name}`, `brush.options {name, params?}`, `brush.delete {name} | {names}`,
+  `brush.duplicate {name, newName?} | {names}`, `brush.freehand`, `object.expandBrush {ids?}`.
 - Variables: `variable.list`, `variable.define {name, kind: text|visibility|image|graph}`, `variable.bind {variable, ids?}`,
   `variable.makeTextDynamic`, `variable.makeVisibilityDynamic`, `variable.makeImageDynamic`, `variable.makeGraphDynamic`,
   `variable.unbind`, `variable.rename`, `variable.delete`, `variable.highlight` (image values are file paths, graph

docs/target-app-parity.md

@@ -599,6 +599,7 @@ Moved from the ROADMAP's "Shipped so far" on 2026-10-10. Update it when a featur
     With a gradient stop or a freeform gradient point selected, Alt-clicking a color swatch in the Swatches panel recolors it instead of the inactive Fill or Stroke.
   - **Strokes:** one stroke-geometry module shared by the canvas, SVG, PDF and Outline Stroke; dotted lines (zero-length dashes draw dots or squares); arrowheads with hollow outlines, tip-on-end or extend-past-end alignment and one opacity for line and head. SVG and PDF export arrowheads, width profiles, brushes and aligned strokes exactly as the canvas draws them; Outline Stroke and the live Outline Stroke effect outline every stroke item as drawn (dashes, heads, profiles, alignment); dashes can be fitted to corners and path ends; width profiles carry through dashes, and their corners take the join. The Stroke panel edits type's character strokes, follows the stroke units (its weight presets are round values in that unit: `0.25 mm`, `0.0625 in`, `1 px`, #426; fields show four decimals in mm, cm and inches, three in points), shows mixed values blank and opens from the Control bar. A width profile library, thirty more arrowheads, and Width Point Edit with multi-select and discontinuous points. Visual bounds and clicks cover the whole painted stroke. Scale Strokes & Effects, Scale Corners and Use Preview Bounds work everywhere, and new art inherits stroke options, a graphic style or the whole last appearance.
   - **Brushes (part of #852):** double-clicking a brush in the Brushes panel (or the panel menu's Brush Options…) opens Calligraphic Brush Options (Name; Angle, Roundness and Size, each Fixed, Random or Pressure with its Variation; live previews of the nib and of a light–heavy–light stroke) or Bristle Brush Options (Shape and the bristle sliders); OK edits the brush and every stroke painted with it. The Paintbrush records the pen pressure along each stroke (kept with the path, saved, and joined when a stroke continues a path); a Calligraphic value on Pressure goes from value − variation at the lightest pressure to value + variation at the heaviest, on the canvas and in SVG, PDF and the other exports. Brushes saved before keep their look. Scatter Brush Options (Size, Spacing, Scatter and Rotation, each Fixed, Random between two values or Pressure from the first at the lightest pressure to the second at the heaviest; Rotation relative to Page or Path), Art Brush Options (Width, Scale Proportionately, Stretch to Fit Stroke Length or Stretch Between Guides with the guides' start and end, the four Directions, Flip Along and Across) and Pattern Brush Options (Scale, Spacing, the five tiles shown, Flip Along and Across, Stretch to fit, Add space to fit or Approximate path) each have Colorization (None, Tints, Tints and Shades, Hue Shift with its Key Color picked from the art's colours) and a live stroke preview; values from files and commands are clamped to their ranges. Still to come: the Art brush's Overlap, auto-generated Pattern brush corners, new tile art picked in Pattern Brush Options, Stylus Wheel, Tilt, Bearing and Rotation, and pen pressure on macOS.
+    In the Brushes panel, Shift-click selects a range of brushes and Ctrl/Cmd-click adds or removes one. Delete Brush and Duplicate Brush then act on all of them (`brush.delete {names}`, `brush.duplicate {names}`).
   - **Appearance:** the Appearance panel's selected row drives every paint, stroke, gradient and transparency edit (`item` on the commands); effects apply to one fill or stroke; per-item Opacity popups, whose blend-mode list and opacity slider stay open inside them (#430; the Control bar's Stroke popover too); Mixed Appearances, Layers target dots and basic-appearance rules. Effects can be reordered, moved between items and copied by dragging; Show All Hidden Attributes; clicking an effect edits it in place; the object thumbnail drags onto art; effects render on type, images, symbols, blends, envelopes, meshes and repeats, and per-item raster effects export. Groups, layers and type have their own fills, strokes and effects (Contents and Characters rows); the Layers panel's target circles target layers, groups and objects; Expand Appearance turns fills, strokes, effects and brushes into objects.
     Fill and stroke paint (Fill, Stroke, None, Apply Last Color and Apply Last Gradient, also on characters selected with the Type tool), the Stroke panel's options, gradient and freeform point edits, Swap Fill and Stroke, Default Fill and Stroke, the Eyedropper, and the Appearance panel's item edits, Clear Appearance, Reduce to Basic Appearance, Remove Item, item reordering and Move Appearance record no undo step when they change nothing.
     A geometry effect on one of type's own fills or strokes reshapes the whole outline that the fill or stroke paints, on the canvas and in exports; PDF, SVG, EPS and the other vector exports write such type as paths. On type that holds inline graphics, those effects are drawn and exported only when the type has a geometry effect or perspective of its own.