M8.3: Liquify Tool Options dialogs, pen pressure and Brush Affects

Double-clicking a Liquify tool opens its Tool Options (dialog liquifyOptions):
the shared Global Brush Dimensions (Width, Height, Angle, Intensity, Use
Pressure Pen), the tool's options (Detail, Simplify with its checkbox, Twirl
Rate, Complexity, Brush Affects, Horizontal/Vertical) and Show Brush Size.
The canvas captures pen pressure from pen/touch force, ui.pointer and MCP
pointer events take `pressure`, and object.liquify takes [x, y, pressure].
Fixes: LiquifyParams::to_json now sends affectAnchors/In/Out; Alt-drag sizes
the brush from its current size (Shift keeps proportions) instead of
collapsing it. Hint-bar text for the seven tools. Registers the MCP Liquify
tests file added in M8.2.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/control-protocol.md

@@ -472,3 +472,10 @@ Mesh… open `envelopeMesh` (`rows`, `cols`, `reset`, and `maintainShape` when r
 `distortLinearGradients`, `distortPatternFills`) with the selected envelope's values, or with nothing selected the
 defaults for new envelopes. They preview live while an envelope is involved, and `ui.dialog.confirm` keeps the result
 as one undo step.
+
+Liquify Tool Options: double-clicking a Liquify tool (`tool.options {tool: "twirl"}`) opens a `liquifyOptions` dialog.
+Its fields are `tool`, the Global Brush Dimensions `width`, `height` (pt), `angle`, `intensity` (%) and `usePressure`,
+then the tool's options `detail`, `simplify` and `simplifyOn` (Warp, Twirl, Pucker, Bloat), `rate` (Twirl),
+`complexity`, `affectAnchors`, `affectIn` and `affectOut` (Scallop, Crystallize, Wrinkle), `horizontal` and
+`vertical` (Wrinkle, %), and `showBrush`. `ui.dialog.confirm` runs `tool.setOption {tool, values}`. `ui.pointer`
+events take `pressure` (0..1, default 1): it is the Liquify intensity while Use Pressure Pen is on.

docs/mcp.md

@@ -1799,3 +1799,21 @@ export (SVG, PDF, EPS, EMF/WMF, DXF).
 {"name":"run_command","arguments":{"command":"object.envelope.options","params":{"fidelity":80,"distortAppearance":true,"distortLinearGradients":true}}}
 {"name":"run_command","arguments":{"command":"object.envelope.info","params":{}}}
 ```
+
+## Liquify tools
+
+The Liquify tools (`warp`, `twirl`, `pucker`, `bloat`, `scallop`, `crystallize`, `wrinkle`) drag a brush over paths:
+the selected ones, or with nothing selected every path the brush passes over. A stroke is one undo step and one
+`object.liquify` journal entry, which an agent can also run directly. Their options (`tool.setOption`) are the Global
+Brush Dimensions shared by the seven tools (`width`, `height` in pt, `angle`, `intensity` 0..1, `usePressure`,
+`showBrush`) and the tool's own: `detail` (1..10); `simplify` (0..100) with `simplifyOn` (Warp, Twirl, Pucker,
+Bloat); `rate` (Twirl, -180..180°); `complexity` (0..15) and `affectAnchors`, `affectIn`, `affectOut` (Scallop,
+Crystallize, Wrinkle: what the brush moves); `horizontal`, `vertical` (Wrinkle, 0..1). Alt-drag sizes the brush from
+its current size (with Shift too it keeps its proportions). With Use Pressure Pen on, each `pointer_gesture` event's
+`pressure` (0..1) is the intensity there, and `object.liquify` takes points as `[x, y, pressure]`.
+
+```json
+{"name":"run_command","arguments":{"command":"tool.setOption","params":{"tool":"bloat","values":{"width":80,"height":80,"usePressure":true}}}}
+{"name":"pointer_gesture","arguments":{"tool":"bloat","events":[{"kind":"down","x":280,"y":150,"pressure":0.3},{"kind":"drag","x":280,"y":200,"pressure":0.8},{"kind":"up","x":280,"y":250}]}}
+{"name":"run_command","arguments":{"command":"object.liquify","params":{"tool":"scallop","points":[[300,150],[300,250]],"complexity":3,"affectAnchors":false}}}
+```