chore: add dev deps and test config

pyproject.toml

@@ -1,13 +1,32 @@
 [project]
 name = "auditui"
-version = "0.1.1"
+version = "0.1.2"
 description = "An Audible TUI client"
 readme = "README.md"
 requires-python = ">=3.10,<3.13"
 dependencies = ["audible>=0.10.0", "httpx>=0.28.1", "textual>=6.7.1"]
 
+[project.optional-dependencies]
+dev = [
+  "coverage[toml]>=7.0",
+  "pytest>=7.0",
+  "pytest-asyncio>=0.23",
+  "httpx>=0.28.1",
+]
+
 [project.scripts]
 auditui = "auditui.cli:main"
 
+[tool.pytest.ini_options]
+testpaths = ["tests"]
+
+[tool.coverage.run]
+branch = true
+source = ["auditui"]
+
+[tool.coverage.report]
+show_missing = true
+skip_covered = true
+
 [tool.uv]
 package = true