Layers: Pattern Fill dialog for new and edited pattern fill layers (#2908) (#2979)

* Layers: Pattern Fill dialog for new and edited pattern fill layers (#2908)

Layer > New Fill Layer > Pattern... created the layer with default
settings and no dialog, and double-clicking a Pattern Fill thumbnail only
opened Properties, which has no pattern controls, so a pattern fill could
not be adjusted after creation.

Both now open Photoshop's Pattern Fill dialog: the pattern swatch picker,
Snap to Origin, Angle, Scale and Link with Layer, previewed live on the
canvas from a document snapshot. OK runs one engine command, so it is one
History step; Cancel changes nothing (a new layer is not created).

- engine: new `layer.fill.pattern.set` (pattern_fill_cmds) edits a Pattern
  Fill's pattern, scale, angle, link and phase in one undo step, validating
  every param; `preview` applies it or `layer.newFillLayer.pattern` to a
  copy of the document for the dialog. `new_fill_layer`'s edit is shared
  as `insert_fill_layer` so the preview is exactly what OK commits.
- ui: pattern_fill_ui (dialog body, OK, canvas preview), routed from the
  menu item (no params) and Layer Content Options; explicit params still
  run the engine directly. Catalog entries for the new strings.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

* Pattern Fill test: pick the swatch picker's Patterns button (main added a Patterns dock tab)

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

---------

Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Co-authored-by: Brandon Thomas <echelon@gmail.com>

docs/control-protocol.md

@@ -93,6 +93,7 @@ store expose and persist the same setting; scripts keep using canonical command
 | `channel.target` / `channel.setVisible` | Channels panel target and eyes (`"composite"`, colour name, alpha index or name, `"quickMask"`). `document.inspect` (and `channel.list`) report `channels`: composite/colour/alpha rows with visibility, channel options, `quickMask`, `target`. Pixel commands without a `target` param follow the targeted channel |
 | `layer.setProps` | `{"layer":id?,"name":…,"visible":…,"opacity":0..1,"blend":"Multiply"}` |
 | `layer.fill.solidColor.set` | `{"layer":id?,"document":id?,"color":"#rrggbb"}`: edit a Solid Color Fill in one undo step; RGB without alpha preserves the fill's alpha. Float RGB arrays and a stored `Color` are also accepted. `document` rejects stale dialog targets. |
+| `layer.fill.pattern.set` | `{"layer":id?,"document":id?,"pattern":id\|name?,"scale":1..1000?,"angle":-180..180?,"link":bool?,"phase":[x,y]?}`: edit a Pattern Fill (the Pattern Fill dialog's OK) in one undo step; omitted values keep the layer's, `phase` `[0,0]` is Snap to Origin. `layer.newFillLayer.pattern` from a menu (no params) and `layer.layerContentOptions` on a Pattern Fill layer open the Pattern Fill dialog. |
 | `layer.layerMask.edit` | `{"layer":id?,"document":id?,"density":0..100?,"feather":0..1000?}`: edit pixel-mask Density (%) and Feather (px) without changing mask pixels, including adjustment masks. At least one setting is required; `document` rejects stale targets. A shared `coalesce` key groups slider updates into one undo step. |
 | `layer.setExpanded` | `{"layer":id?,"expanded":bool?,"all":bool?}`: open/close a group in the Layers panel (no `expanded`: toggle; `all`: every group). A view change saved with the document (PSD open/closed folder), not an undo step; `document.inspect` reports `expanded` on groups |
 | `layer.newAdjustmentLayer.hueSaturation` | `{"hue":30,"saturation":10}` |