Initial snapshot: hand motion pipeline (Dyn-HaMR + dex-retargeting + SPIDER)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

third_party/spider/docs/index.md

@@ -0,0 +1,49 @@
+---
+layout: home
+
+hero:
+  name: "SPIDER"
+  text: "Scalable Physics-Informed DExterous Retargeting"
+  tagline: A general framework for physics-based retargeting from human to diverse robot embodiments
+  image:
+    src: /figs/teaser.png
+    alt: SPIDER
+  actions:
+    - theme: brand
+      text: Get Started
+      link: /guide/quick-start
+    - theme: alt
+      text: View on GitHub
+      link: https://github.com/facebookresearch/spider
+
+features:
+  - icon: 🔬
+    title: Physics-Based
+    details: First general physics-based retargeting pipeline for both dexterous hand and humanoid robot manipulation
+
+  - icon: ⚡
+    title: Fast Simulation
+    details: GPU-accelerated batched simulation with MuJoCo Warp achieving 10-20x speedup over sequential execution
+
+  - icon: 📊
+    title: Rich Datasets, Robots and Simulators
+    details: Works with 6+ datasets out of the box including GigaHand, Hot3D, OakInk, and more. Supports 9+ robot embodiments including dexterous hands (Allegro, Inspire, Xhand) and humanoid robots (G1, H1, T1). Supports multiple simulators including MuJoCo Warp, Genesis, and HDMI.
+
+  - icon: 🔄
+    title: Sim2Real Ready
+    details: Optimized trajectories can be directly deployed to real-world robots with minimal adjustments
+---
+
+## Quick Example
+
+```bash
+# Clone example datasets
+git clone https://huggingface.co/datasets/retarget/retarget_example example_datasets
+
+# Install with uv
+uv sync --python 3.12
+pip install --ignore-requires-python --no-deps -e .
+
+# Run retargeting
+uv run examples/run_mjwp.py
+```