Python: [BREAKING] added SerializationMixin and applied to contents, agents, chat client… (#1012)

* added SerializationMixin and applied to contents, agents, chat clients, removed AFBaseModel

* fix annotations type

* mypy fixes

* fix tests

* fix serializable subvalues and added large docstring

* updated indents in code block

* fixed exported urls

python/packages/lab/pyproject.toml

@@ -54,6 +54,27 @@ math = [
   "sympy>=1.13.0",
 ]
 
+[dependency-groups]
+dev = [
+    "uv>=0.8.2,<0.9.0",
+    "pre-commit >= 3.7",
+    "ruff>=0.11.8",
+    "pytest>=8.4.1",
+    "pytest-asyncio>=1.0.0",
+    "pytest-cov>=6.2.1",
+    "pytest-env>=1.1.5",
+    "pytest-xdist[psutil]>=3.8.0",
+    "pytest-timeout>=2.3.1",
+    "pytest-retry>=1",
+    "mypy>=1.16.1",
+    "pyright>=1.1.402",
+    #tasks
+    "poethepoet>=0.36.0",
+    "rich",
+    "tomli",
+    "tomli-w",
+]
+
 [project.scripts]
 gaia_viewer = "agent_framework_lab_gaia:viewer_main"
 lightning = "agent_framework_lab_lightning:main"