Crop editors: spell Center the US way

The row next to Fill, Feather and Resize said Centre. It now says Center,
and so do the two button tooltips and the three crop help pages. Code
names and comments are unchanged, since nobody sees them.

js/docs/AUSBOSS_NODES_ImageCropRotatePad.md

@@ -37,7 +37,7 @@ From top to bottom:
 - **The ratio row**: the orientation button, the ratios (1:1, 4:3, 3:2, 16:9,
   21:9) and the padlock.
 - **Fit** (crop | pad) and **Divisible by**.
-- **Fill**, **Feather**, **Resize** and the two **Centre** buttons.
+- **Fill**, **Feather**, **Resize** and the two **Center** buttons.
 - **Open editor**, **Reset crop** and **Reset**.
 
 Crop and padding have no number boxes. You set them by dragging, and the size
@@ -74,7 +74,7 @@ until you tap one.
   size. Over the picture, the cursor and small arrows show which ways it can go.
 - Rotating keeps a lit ratio: the padding follows the turned picture.
 
-### Corner handles and Centre
+### Corner handles and Center
 
 The four orange corners outside the picture make the whole canvas bigger or
 smaller and keep its shape: drag one out to add room on two sides at once, for
@@ -84,7 +84,7 @@ sides at once, so the picture keeps its place in the middle. You can press or le
 go of Alt during the drag. A corner stops when one of its two sides has no padding
 left to take away.
 
-The two **Centre** buttons next to Fill, Feather and Resize put the picture in
+The two **Center** buttons next to Fill, Feather and Resize put the picture in
 the middle of the canvas: one side to side, one top to bottom. They move padding from
 one side to the other, so the canvas keeps its size and a lit ratio stays lit. A
 button is dimmed when the picture is already in the middle or that way has no
@@ -210,7 +210,7 @@ for fine steps). The editor adds a few things the node does not show:
 - **Rotate → Degrees** (`rotation_degrees`): type an exact turn, clockwise.
   Each step is 1°, or 0.1° with Shift. **Reset rotation** sets it back to 0.
 - **Padding & mask → Reset padding** removes all padding. The same section has
-  Fill, Feather, Divisible by and a **Centre** row.
+  Fill, Feather, Divisible by and a **Center** row.
 - **Resize output → Method** (`resize_method`): how the resize samples the
   picture. `lanczos`, the default, is the sharp one.
 - **More**: ratios you added in `ausboss_presets.json` that no button shows.
@@ -254,7 +254,7 @@ The editor's right side holds the stitcher's settings, the same as on the clip n
     number, or a colour name. Anything it cannot read becomes mid-gray.
 - **Corners.** A corner follows the pointer along the canvas diagonal, and the
   shape it keeps is the canvas before **Divisible by** adds its fill. With
-  Divisible by on, **Centre** counts that strip on the right and bottom, so the
+  Divisible by on, **Center** counts that strip on the right and bottom, so the
   bands you see come out even.
 - **Resize.** It works like core's *Scale Image to Total Pixels*: the budget is
   `megapixels × 1024 × 1024`, the shape is kept, and each side rounds to a

js/docs/AUSBOSS_NODES_VideoCropRotatePad.md

@@ -36,7 +36,7 @@ Rotation, crop, padding, feathering, fill, **Divisible by**, the megapixel resiz
 
 The handles work on both the node and the editor. Drag an orange corner to make
 the canvas bigger or smaller in its own shape (hold **Alt**, Option on a Mac, to
-change all four sides at once), and press **Centre** next to Fill and Feather to
+change all four sides at once), and press **Center** next to Fill and Feather to
 put the frame in the middle, side to side or top to bottom. Both work as on the
 image node. The ratio buttons, **Fit**,
 the padlock and the orientation button work as on the image node: a tap pads (or,

js/docs/AUSBOSS_NODES_VideoCropRotatePadClip.md

@@ -76,7 +76,7 @@ model that paints black regions.
 Crop squares, padding diamonds, the orange corners and the rotation handle also
 work directly on the node preview. A corner makes the canvas bigger or smaller in
 its own shape, for example to zoom out evenly before a video outpaint; hold **Alt**
-(Option on a Mac) to change all four sides at once. **Centre**, next to Fill and
+(Option on a Mac) to change all four sides at once. **Center**, next to Fill and
 Feather, puts the clip in the middle of the canvas side to side or top to bottom
 without changing the canvas size. The graph still owns wheel zoom and middle-button
 pan. Tap a ratio

js/shared/transform_editor.mjs

@@ -962,8 +962,8 @@ function buildAspectModeRow(state, { alignment: withAlignment = true } = {}) {
 // (centredPadding), so the canvas keeps its size and a lit ratio stays lit.
 // The node face and the editor's Padding section each get a pair.
 const CENTRE_AXES = [
-  ["x", "Centre side to side", "left and right", "right"],
-  ["y", "Centre top to bottom", "top and bottom", "bottom"],
+  ["x", "Center side to side", "left and right", "right"],
+  ["y", "Center top to bottom", "top and bottom", "bottom"],
 ];
 
 function centrePicture(state, axis) {
@@ -1212,7 +1212,7 @@ function buildCanvasRow(state) {
   // span, not a label: a label passes a click on its text to the first button.
   const centre = buildCentreButtons(state);
   const centreLabel = createElement("span", "ausboss-transform-centre-label");
-  centreLabel.append(createElement("span", "", "Centre"), centre.root);
+  centreLabel.append(createElement("span", "", "Center"), centre.root);
   row.append(centreLabel);
   const sync = () => {
     fill.value = normalizeColor(value(node, "fill_color", "#808080"));
@@ -1867,7 +1867,7 @@ function buildControls(state, sidebar) {
   // A div, not a label: a label would pass a click on its text to the first button.
   const centre = buildCentreButtons(state);
   const centreRow = createElement("div", "ausboss-transform-centre-row");
-  centreRow.append(createElement("span", "", "Centre"), centre.root);
+  centreRow.append(createElement("span", "", "Center"), centre.root);
   padSection.append(centreRow);
   state.editorSyncs.push(centre.sync);
   const resetPad = createElement("button", "", "Reset padding"); resetPad.title = "Remove all padding.";