M4.20: Document Setup with bleed, transparency grid, paper and type options

File > Document Setup is a tabbed dialog over one engine command,
document.setup (no params: a query; any keys: one undo step;
document.setUnits stays as the units alias).

- General: units, bleed (four sides with a link toggle), Edit Artboards,
  Show Images in Outline Mode (greyscale pixels under the frame),
  Highlight Substituted Fonts/Glyphs (pink boxes on screen only).
- Transparency: grid size and colour presets or custom colours, Simulate
  Colored Paper, the flattener preset (built-in or saved) and Discard
  White Overprint (Overprint Preview keeps white overprints visible).
- Type: language with its quotes, Use Typographer's Quotes for the Type
  tool and Smart Punctuation, superscript/subscript size and position and
  small caps size (Character panel position/smallCaps; changing the
  setup restyles the text in the same undo step), text export (SVG text
  as text or outlines by default).
- The canvas draws a red bleed outline and the grid in the document's
  colours and cell size as one textured quad, also in rotated views; a
  white Background Contents exports raster formats opaque.

Model: Document.setup (DocSetup, defaulted, skipped when default) and
CharStyle position/small_caps; old files load unchanged.
tests_transparencygrid's helper now finds the grid by its texture (the
grid is one textured mesh instead of per-cell rectangles).

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

docs/control-protocol.md

@@ -204,3 +204,11 @@ length preferences in `preferences`) show in the General unit (the active docume
 document). Through `ui.dialog.set` a number is in points and a string may carry its unit (`"10 mm"`; a bare number in a
 string is points). The `preferences` dialog's `unitsGeneral` starts as the active document's units, and OK sets them.
 `newDocument` has `units` (a unit label; print presets start in `unitsGeneral`, screen presets in Pixels).
+
+Document Setup: File → Document Setup… (`file.documentSetup`, Cmd+Alt+P) opens the `documentSetup` dialog. Its fields
+are what `document.setup` reports (`units`, `bleed` [top, bottom, left, right] in pt, `outlineImages`,
+`highlightSubstitutedFonts`, `highlightSubstitutedGlyphs`, `gridSize`, `gridColors`, `simulatePaper`, `flattenerPreset`,
+`discardWhiteOverprint`, `language`, `quotes`, `typographersQuotes`, `superscript`, `subscript`, `smallCapsSize`,
+`exportText`, `backgroundContents`) plus `tab` (`General`, `Transparency` or `Type`) and `bleedLinked`.
+`ui.dialog.confirm` runs `document.setup` with them as one undo step; a bad value answers with an error and the dialog
+stays open.

docs/mcp.md

@@ -779,3 +779,16 @@ a string with a unit. Unit names: `Points`, `Picas`, `Inches`, `Millimeters`, `C
 ```json
 {"name":"run_command","arguments":{"command":"prefs.set","params":{"key":"unitsGeneral","value":"millimeters"}}}
 ```
+
+## Document Setup
+
+`document.setup` with no params reports the document setup: units, the bleed ([top, bottom, left, right] in pt, drawn
+as a red outline around each artboard), the transparency grid (size and two colours; the first is also the simulated
+paper colour), the flattener preset and Discard White Overprint (Overprint Preview keeps white overprints visible while
+it is on), the type options (language and its quotes, Use Typographer's Quotes for typed quotes, superscript, subscript
+and small caps proportions, SVG text export) and the background contents (white: raster exports are white behind the
+art). Pass any of these keys to change them in one undo step; `document.setUnits` stays as an alias for `units`.
+
+```json
+{"name":"run_command","arguments":{"command":"document.setup","params":{"gridColors":"Blue","gridSize":"large","language":"German","bleed":9}}}
+```