docs: create initial AGENTS.md noting uv package management

Co-authored-by: deviantintegral <255023+deviantintegral@users.noreply.github.com>

Author: Copilot

AGENTS.md

@@ -0,0 +1,28 @@
+# Agents
+
+## Package Management
+
+This project uses [`uv`](https://docs.astral.sh/uv/) for package management. Do **not** use `pip` directly.
+
+Install dependencies with:
+
+```bash
+uv sync --dev
+```
+
+Add packages with:
+
+```bash
+uv add <package>
+```
+
+## Development
+
+```bash
+# Lint and type-check
+uv run ruff check .
+uv run mypy src/
+
+# Run tests
+uv run pytest
+```