Feature(UI): Add text tool to canvas

docs/development/canvas-text-tool.md

@@ -0,0 +1,35 @@
+# Canvas Text Tool
+
+## Overview
+
+The canvas text workflow is split between a Konva module that owns tool state and a React overlay that handles text entry.
+
+- `invokeai/frontend/web/src/features/controlLayers/konva/CanvasTool/CanvasTextToolModule.ts`
+  - Owns the tool, cursor preview, and text session state (including the cursor "T" marker).
+  - Manages dynamic cursor contrast, starts sessions on pointer down, and commits sessions by rasterizing the active text block into a new raster layer.
+- `invokeai/frontend/web/src/features/controlLayers/components/Text/CanvasTextOverlay.tsx`
+  - Renders the on-canvas editor as a `contentEditable` overlay positioned in canvas space.
+  - Syncs keyboard input, suppresses app hotkeys, and forwards commits/cancels to the Konva module.
+- `invokeai/frontend/web/src/features/controlLayers/components/Text/TextToolOptions.tsx`
+  - Provides the font dropdown, size slider/input, formatting toggles, and alignment buttons that appear when the Text tool is active.
+
+## Rasterization pipeline
+
+`renderTextToCanvas()` (`invokeai/frontend/web/src/features/controlLayers/text/textRenderer.ts`) converts the editor contents into a transparent canvas. The Text tool module configures the renderer with the active font stack, weight, styling flags, alignment, and the active canvas color. The resulting canvas is encoded to a PNG data URL and stored in a new raster layer (`image` object) with a transparent background.
+
+Layer placement preserves the original click location:
+
+- The session stores the anchor coordinate (where the user clicked) and current alignment.
+- `calculateLayerPosition()` calculates the top-left position for the raster layer after applying the configured padding and alignment offsets.
+- New layers are inserted directly above the currently-selected raster layer (when present) and selected automatically.
+
+## Font stacks
+
+Font definitions live in `invokeai/frontend/web/src/features/controlLayers/text/textConstants.ts` as ten deterministic stacks (sans, serif, mono, rounded, script, humanist, slab serif, display, narrow, UI serif). Each stack lists system-safe fallbacks so the editor can choose the first available font per platform.
+
+To add or adjust fonts:
+
+1. Update `TEXT_FONT_STACKS` with the new `id`, `label`, and CSS `font-family` stack.
+2. If you add a new stack, extend the `TEXT_FONT_IDS` tuple and update the `canvasTextSlice` schema default (`TEXT_DEFAULT_FONT_ID`).
+3. Provide translation strings for any new labels in `public/locales/*`.
+4. The editor and renderer will automatically pick up the new stack via `getFontStackById()`.

invokeai/frontend/web/public/locales/en.json

@@ -2371,7 +2371,19 @@
             "bbox": "Bbox",
             "move": "Move",
             "view": "View",
-            "colorPicker": "Color Picker"
+            "colorPicker": "Color Picker",
+            "text": "Text"
+        },
+        "text": {
+            "font": "Font",
+            "size": "Size",
+            "bold": "Bold",
+            "italic": "Italic",
+            "underline": "Underline",
+            "strikethrough": "Strikethrough",
+            "alignLeft": "Align Left",
+            "alignCenter": "Align Center",
+            "alignRight": "Align Right"
         },
         "filter": {
             "filter": "Filter",

invokeai/frontend/web/src/app/store/store.ts

@@ -23,6 +23,7 @@ import { changeBoardModalSliceConfig } from 'features/changeBoardModal/store/sli
 import { canvasSettingsSliceConfig } from 'features/controlLayers/store/canvasSettingsSlice';
 import { canvasSliceConfig } from 'features/controlLayers/store/canvasSlice';
 import { canvasSessionSliceConfig } from 'features/controlLayers/store/canvasStagingAreaSlice';
+import { canvasTextSliceConfig } from 'features/controlLayers/store/canvasTextSlice';
 import { lorasSliceConfig } from 'features/controlLayers/store/lorasSlice';
 import { paramsSliceConfig } from 'features/controlLayers/store/paramsSlice';
 import { refImagesSliceConfig } from 'features/controlLayers/store/refImagesSlice';
@@ -62,6 +63,7 @@ const log = logger('system');
 const SLICE_CONFIGS = {
   [canvasSessionSliceConfig.slice.reducerPath]: canvasSessionSliceConfig,
   [canvasSettingsSliceConfig.slice.reducerPath]: canvasSettingsSliceConfig,
+  [canvasTextSliceConfig.slice.reducerPath]: canvasTextSliceConfig,
   [canvasSliceConfig.slice.reducerPath]: canvasSliceConfig,
   [changeBoardModalSliceConfig.slice.reducerPath]: changeBoardModalSliceConfig,
   [dynamicPromptsSliceConfig.slice.reducerPath]: dynamicPromptsSliceConfig,
@@ -87,6 +89,7 @@ const ALL_REDUCERS = {
   [api.reducerPath]: api.reducer,
   [canvasSessionSliceConfig.slice.reducerPath]: canvasSessionSliceConfig.slice.reducer,
   [canvasSettingsSliceConfig.slice.reducerPath]: canvasSettingsSliceConfig.slice.reducer,
+  [canvasTextSliceConfig.slice.reducerPath]: canvasTextSliceConfig.slice.reducer,
   // Undoable!
   [canvasSliceConfig.slice.reducerPath]: undoable(
     canvasSliceConfig.slice.reducer,