Fix #388: Pencil, Paintbrush, Smooth, Blob Brush and Eraser Tool Options on double-click

The five freehand tools keep options (Fidelity, fill, the two
tolerances, the brush size) that last across tool switches and are
saved with the preferences, but nothing in the window showed or changed
them: a double-click on the tool's button answered "the pencil tool has
no options", which the toolbar drops. It now opens a Tool Options dialog
with the options the tool has, and OK sets them with tool.setOption. The
dialog's strings are in the Japanese, Chinese (both scripts) and
Brazilian Portuguese catalogs.

Co-Authored-By: Claude Sonnet 5.5 <[email protected]>

docs/control-protocol.md

@@ -523,6 +523,12 @@ then the tool's options `detail`, `simplify` and `simplifyOn` (Warp, Twirl, Puck
 `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.
 
+Freehand Tool Options: double-clicking the Pencil, Paintbrush, Smooth, Blob Brush or Eraser tool
+(`tool.options {tool: "pencil"}`) opens a `freehandOptions` dialog. Its fields are `tool` and the options the tool
+keeps: `fidelity` (pt; Pencil, Paintbrush, Smooth), `fill` (Pencil, Paintbrush), `closeWithin` and `editWithin` (screen
+pixels, 0 turns it off; Pencil, Paintbrush) and `size` (pt; Blob Brush, Eraser). `ui.dialog.confirm` runs
+`tool.setOption {tool, values}`.
+
 `ui.pointer` events also take `holdMs` (0..60000): the pointer then holds still that long, button down, before the
 next event. Twirl, Pucker and Bloat keep applying while held (a repeat of the last point every 0.1 s), exactly as
 for the same time held with the mouse. Liquify leaves type, symbols, images, graphs, meshes, envelopes, repeats and