feat: Add GitHub Actions workflow for building and testing the Depth Anything 3 extension

- Create a build workflow in `.github/workflows/build.yml` to automate the build process.
- Configure Python environment and install dependencies.
- Add steps for running tests and packaging the extension.

chore: Initialize project metadata and dependencies for Depth Anything 3

- Add `pyproject.toml` for project configuration and dependencies.
- Include optional dependencies for app and gs functionalities.
- Define project scripts and metadata.

chore: Add requirements file for Depth Anything 3 dependencies

- Create `requirements.txt` listing all necessary packages for the project.

feat: Implement export utility functions for Depth Anything 3

- Create `src/depth_anything_3/utils/export/__init__.py` to handle various export formats.
- Implement functions for exporting predictions in different formats.

feat: Add ray utility functions for homography estimation

- Create `src/depth_anything_3/utils/ray_utils.py` with functions for computing optimal rotation and homography using RANSAC.

feat: Implement vendor preparation script

- Add `prepare_vendor.py` to manage third-party dependencies and artifacts.
- Include functions for downloading and verifying artifacts based on a lock file.

test: Add unit tests for vendor preparation script

- Create `tests/test_prepare_vendor.py` to test artifact downloading and verification.
- Implement tests for handling hash mismatches and unsupported platforms.

chore: Add vendor lock file for dependency management

- Create `vendor.lock.toml` to define artifacts and platforms for the project.

.github/workflows/build.yml

@@ -0,0 +1,41 @@
+name: 构建扩展
+
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: 检出代码
+        uses: actions/checkout@v6
+
+      - name: 配置 Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: "3.12"
+          cache: pip
+
+      - name: 安装测试依赖
+        run: python -m pip install numpy pytest
+
+      - name: 准备 Vendor
+        run: python prepare_vendor.py
+
+      - name: 运行测试
+        run: python -m pytest
+
+      - name: 构建扩展
+        run: python pack.py
+
+      - name: 上传扩展包
+        uses: actions/upload-artifact@v7
+        with:
+          name: SnapForm
+          path: dist/*.zip
+          if-no-files-found: error