Architecture: TabHeader and panAndZoom (#85); Keyboard: hold Alt for Pick in the tilemap panel

Architecture.md

@@ -87,7 +87,7 @@ src/editor/            App → Editor (layout + ticker), PlaySession (the run),
                        EditorRun (run in editor), state, actions, shortcuts, debugHook, autosave,
                        fileImport (drop/paste) → assetImport (one upload pipeline, an ImportKind per sort) ← textureImport / fontImport / soundImport,
                        FilePicker (the shared "+ → Texture / Font / Sound" dialog; ImagePicker/FontPicker/SoundPicker only describe their row),
-                       framing (fit/marquee/snap maths), FormDialog (the small modal forms: label column, Cancel + confirm, one open at a time), AssetTabEditor (the shared shell of the asset tabs),
+                       framing (fit/marquee/snap maths), FormDialog (the small modal forms: label column, Cancel + confirm, one open at a time), AssetTabEditor (the shared shell of the asset tabs), TabHeader (the bar across the top of a tab – asset tabs, Plugins tab, NodeBoard),
                        TabStrip + tabRow (the tab row and what it does when the tabs outgrow it; plugin tabs are appended at run time)
 src/editor/plugins/    startPlugins (list, import, host) → loader (PluginManager: order, checks, switching on and off, what became of each file), pluginApi (API v1, the per-plugin scope), PluginsPane (the Plugins tab), NodeBoard (api.ui)
 src/editor/viewport/   WorldViewport base → FreeViewport (a camera of its own: fit, pan, wheel zoom) → SceneViewport, PreviewCanvas;
@@ -99,7 +99,7 @@ src/editor/inspector/  Inspector panel, host (what a section builds into), field
 src/editor/panels/     AssetPanel, assetMenu (the two groups of the + menu), HierarchyPanel, Toolbar,
                        TilemapPanel (tools, tiles and layers of the one selected tilemap, beside the scene view, #142;
                        painting itself is SceneViewport)
-src/editor/graph/      GraphEditor (header + picker), GraphCanvas, graphView (zoom limits, grid, wheel zoom – shared with NodeBoard), EdgeLayer (curves and fold marks), graphMenus,
+src/editor/graph/      GraphEditor (header + picker), GraphCanvas, graphView (zoom limits, grid, panAndZoom – shared with NodeBoard and the Tile tab's TileCanvas), EdgeLayer (curves and fold marks), graphMenus,
                        NodeView, NodePalette + paletteEntries (which also ranks a search), folding (hidden links, collapsed nodes), Breadcrumb + trail (the path into nested behaviors), beads (the run's pulses),
                        AnnotationView + annotationDrag (groups and comments: what a drag carries, each thing moved once)
 src/editor/container/  ContainerEditor (header + picker), ContainerCanvas (a SceneViewport on a template)

Keyboard.md

@@ -13,4 +13,4 @@ value is integral by nature (frame rectangles, the slice dialog, a camera's view
 size, the key-repeat milliseconds, the index and count ports of list and text nodes), which set
 `NumberField`'s `decimals: 0` and show plain whole numbers · viewport: wheel zooms,
 middle-drag or `Shift`+drag pans, drag on empty space rubber-bands, `Ctrl`/`Shift`-click toggles an
-object in the selection (hierarchy rows too).
+object in the selection (hierarchy rows too) · tilemap panel: holding `Alt` switches to Pick – a click takes that cell's tile from the active layer – and releasing it brings back the tool before ([Tilemaps](Tilemaps)).