chore(dev/timeline-layers): wire example into workspace + local dev setup

- Add dev/timeline-layers/examples/* to root workspace glob so yarn
  resolves the package correctly
- Add vite.config.local.mjs (aliases @deck.gl-community/timeline-layers
  to src/ so dist/ is never stale during dev)
- Fix tsconfig.json extends depth (examples/ moved one level deeper vs
  original PR path)
- Update example README with prototype video + end-goal screenshot from
  PR #379, start-local instructions, and context links to #379/#517/#38

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: charlieforward9

dev/timeline-layers/examples/timeline-layer/README.md

@@ -1,6 +1,14 @@
 # Timeline Layer Example
 
-An interactive timeline visualization built with `@deck.gl-community/timeline-layers`.
+An interactive GPU-accelerated timeline built with `@deck.gl-community/timeline-layers` — a deck.gl `CompositeLayer` that replaces DOM-driven timelines and handles hundreds of thousands of datapoints without lag.
+
+### Prototype
+
+https://github.com/user-attachments/assets/95006924-913f-4025-a0ef-6d74b336ca67
+
+### End Goal
+
+<img width="2560" height="1531" alt="Timeline end goal" src="https://github.com/user-attachments/assets/d6b52261-4d03-487d-8bba-e01b9035be7a" />
 
 ## Features
 
@@ -14,25 +22,31 @@ An interactive timeline visualization built with `@deck.gl-community/timeline-la
 ## Usage
 
 ```bash
+# Against installed packages
 yarn start
-```
 
-Open [http://localhost:5173](http://localhost:5173)
+# Against local source (dev)
+yarn start-local
+```
 
 ## API
 
-Import `TimelineLayer` from `@deck.gl-community/timeline-layers`:
-
 ```ts
 import {TimelineLayer} from '@deck.gl-community/timeline-layers';
 
-const layer = new TimelineLayer({
-  data: tracks,          // TimelineTrack[]
-  timelineStart: 0,      // start of full range (ms)
-  timelineEnd: 60000,    // end of full range (ms)
-  currentTimeMs: 5000,   // current playhead position
-  onClipClick: ({clip, track}) => console.log('clicked', clip.label)
+new TimelineLayer({
+  data: tracks,           // TimelineTrack[]
+  timelineStart: 0,       // start of full range (ms)
+  timelineEnd: 60_000,    // end of full range (ms)
+  currentTimeMs: 5_000,   // current playhead position
+  onClipClick: ({clip, track}) => console.log('clicked', clip.label),
+  onViewportChange: (startMs, endMs) => setViewport({startMs, endMs}),
+  onZoomChange: (zoom) => setZoom(zoom)
 });
 ```
 
-See `TimelineLayerProps` for the full API reference.
+See [`TimelineLayerProps`](../../src/layers/timeline-layer/timeline-types.ts) for the full API reference.
+
+## Context
+
+Originally prototyped in PR [#379](https://github.com/visgl/deck.gl-community/pull/379), refined in PR [#517](https://github.com/visgl/deck.gl-community/pull/517). Lives in `dev/timeline-layers` until promoted to `modules/` — tracked in [#38](https://github.com/visgl/deck.gl-community/issues/38).

dev/timeline-layers/examples/timeline-layer/tsconfig.json

@@ -1,4 +1,4 @@
 {
-    "extends": "../../../tsconfig.json",
+    "extends": "../../../../tsconfig.json",
     "include": ["./*.tsx", "./*.ts"]
 }

dev/timeline-layers/vite.config.local.mjs

@@ -0,0 +1,35 @@
+// Allows examples in dev/timeline-layers/examples/ to be built against
+// the source code in this repo instead of installed node_modules.
+
+import {defineConfig} from 'vite';
+import {getOcularConfig} from '@vis.gl/dev-tools';
+import {join} from 'path';
+
+const rootDir = join(__dirname, '../..');
+
+/** https://vitejs.dev/config/ */
+export default defineConfig(async () => {
+  const {aliases} = await getOcularConfig({root: rootDir});
+
+  return {
+    resolve: {
+      alias: {
+        ...aliases,
+        '@deck.gl-community/timeline-layers': join(rootDir, './dev/timeline-layers/src'),
+        '@deck.gl': join(rootDir, './node_modules/@deck.gl'),
+        '@luma.gl': join(rootDir, './node_modules/@luma.gl'),
+        '@math.gl': join(rootDir, './node_modules/@math.gl'),
+        '@loaders.gl': join(rootDir, './node_modules/@loaders.gl'),
+        'react': join(rootDir, './node_modules/react'),
+        'react-dom': join(rootDir, './node_modules/react-dom'),
+      }
+    },
+    server: {
+      open: true,
+      port: 8080
+    },
+    optimizeDeps: {
+      esbuildOptions: {target: 'es2020'}
+    }
+  };
+});

package.json

@@ -14,6 +14,7 @@
   "workspaces": [
     "modules/*",
     "dev/*",
+    "dev/timeline-layers/examples/*",
     "examples/**"
   ],
   "scripts": {