feat: initial implementation of Datacat

- Add project structure with UV/hatch build system
- Implement config module (env vars + YAML file support)
- Implement collector module for pylitterbot integration
- Implement metrics module for Datadog submission
- Support LR3, LR4, and Feeder Robot metrics
- Add event emission for state changes
- Add CLI with --once mode for single collection

pyproject.toml

@@ -0,0 +1,29 @@
+[project]
+name = "datacat"
+version = "0.1.0"
+description = "Collect metrics from Whisker Litter Robot devices and submit to Datadog"
+readme = "README.md"
+requires-python = ">=3.12"
+dependencies = [
+    "pylitterbot>=2025.0.0",
+    "datadog>=0.50.0",
+    "pyyaml>=6.0",
+    "python-dotenv>=1.0.0",
+]
+
+[project.scripts]
+datacat = "datacat:main"
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[tool.hatch.build.targets.wheel]
+packages = ["src/datacat"]
+
+[tool.ruff]
+line-length = 100
+target-version = "py312"
+
+[tool.ruff.lint]
+select = ["E", "F", "I", "N", "W", "UP"]