Flatten to three packages + extract mizan-runtime

packages/
  mizan-runtime/   Framework-agnostic state engine (~150 lines)
                   Context registry, batched invalidation, fetch primitives
  mizan-django/    Django server adapter (was packages/mizan-rpc/adapters/django/)
                   Codegen moved to mizan-django/generate/
  mizan-react/     React adapter (was packages/mizan-csr/adapters/react/)

Removed premature abstractions: mizan-ast, mizan-schema, mizan-rpc,
mizan-csr, mizan-ssr stub packages. The actual architecture is three
concrete packages, not five abstract layers.

mizan-runtime implements the v1 spec: registerContext with params,
scoped invalidation via microtask batching, server-driven invalidation
from mutation responses, mizanFetch for context bundles, mizanCall for
mutations.

264 Django + 33 React tests pass.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/mizan-django/pyproject.toml

@@ -0,0 +1,46 @@
+[project]
+name = "mizan"
+version = "1.0.1"
+description = "Django + React server functions framework"
+readme = "README.md"
+requires-python = ">=3.10"
+dependencies = [
+    "django>=5.0",
+    "django-ninja>=1.0",
+    "django-readers>=2.0",
+    "pydantic>=2.0",
+    "PyJWT>=2.0",
+]
+
+[project.optional-dependencies]
+channels = [
+    "channels>=4.0",
+    "channels-redis>=4.0",
+]
+allauth = [
+    "django-allauth>=65.0",
+]
+webauthn = [
+    "fido2>=2.0",
+]
+shapes = [
+    "django-readers>=2.0",
+]
+dev = [
+    "pytest>=8.0",
+    "pytest-django>=4.9",
+]
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[tool.hatch.build.targets.wheel]
+packages = ["src/mizan"]
+
+[tool.pytest.ini_options]
+DJANGO_SETTINGS_MODULE = "tests.settings"
+pythonpath = ["src", "."]
+testpaths = ["src/mizan/tests"]
+python_classes = ["*Tests", "*Test", "Test*"]
+python_functions = ["test_*"]