Restructure tree by role; rename mizan-runtime → mizan-base

packages/ flattens into:
  backends/   server protocol adapters (mizan-django, mizan-ts)
  frontends/  client kernel + framework adapters (mizan-base, mizan-react, mizan-vue, mizan-svelte)
  workers/    runtime workers (mizan-ssr)
  cores/      shared language-level primitives (empty for now; mizan-python forthcoming)

The frontend kernel (was packages/mizan-runtime, now frontends/mizan-base) is
renamed to reflect its role — it's the shared base that frontend adapters
depend on directly. Reflects the substrate position that per-framework adapters
wrap a single shared kernel; codegen targets the adapter, not the raw kernel.

Path updates landed in: Makefile, two Gitea workflows, Dockerfile.test, four
example/harness config files, .claude/settings.local.json, four docs
(CLAUDE/ISSUES/ROADMAP/AFI_ARCHITECTURE), four codegen templates (stage1 +
react/vue/svelte adapters), and three package.jsons (the mizan-base rename
plus mizan-vue/svelte peerDeps).

Generated files under examples/django-react-site/harness/src/api/ still
reference @mizan/runtime — left as-is; they're regenerated artifacts and
the harness is non-functional pending the React wrapper-layer codegen.

Also folded in a pre-existing fix: the Gitea workflows had
working-directory: react / django pointing at a layout that predates
packages/, never updated.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

backends/mizan-django/pyproject.toml

@@ -0,0 +1,49 @@
+[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]
+cache = [
+    "redis>=5.0",
+]
+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_*"]