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-react/src/index.ts

@@ -0,0 +1,115 @@
+/**
+ * mizan - Django Server Functions Client
+ *
+ * Frontend client for Django server functions.
+ * Server functions are the core primitive - accessed via React hooks.
+ *
+ * Two-layer architecture:
+ *
+ * 1. Library layer (this package) - Generic name-based API
+ *    Used by libraries like Allauth that need to call functions by name.
+ *
+ *    import { useMizan, useMizanContext, useMizanCall } from 'mizan'
+ *    const user = useMizanContext('current_user')
+ *    const call = useMizanCall('update_profile')
+ *
+ * 2. Generated layer (@/api) - Typed project-specific API
+ *    Used by product code for type-safe hooks.
+ *
+ *    import { useCurrentUser, useUpdateProfile } from '@/api'
+ *    const user = useCurrentUser()
+ *    const updateProfile = useUpdateProfile()
+ *
+ * The generated code wraps MizanProvider and adds type-safe hooks.
+ */
+
+// ============================================================================
+// React Context & Hooks (primary API)
+// ============================================================================
+
+export {
+    // Provider
+    MizanProvider,
+    type MizanProviderProps,
+    type MizanHydration,
+
+    // Hooks (generic name-based API for libraries)
+    useMizan,
+    useMizanContext,
+    useMizanCall,
+    useMizanStatus,
+    usePush,
+
+    // Types
+    type MizanContextValue,
+    type ConnectionStatus,
+    type PushMessage,
+    type PushListener,
+    type ContextStore,
+    type Transport,
+
+    // Legacy aliases (deprecated, for migration)
+    DjangoContext,
+    useDjango,
+    useDjangoStatus,
+    useServerFunction,
+    type DjangoContextValue,
+    type DjangoContextProps,
+} from './context'
+
+// ============================================================================
+// HTTP Client (for SSR or non-React usage)
+// ============================================================================
+
+export {
+    httpFunctionCall,
+    createDjangoCSRClient,
+    createDjangoSSRClient,
+    ensureDjangoSession,
+    Auth,
+    type DjangoHTTPClient,
+    type CSRClientConfig,
+    type JWTClientConfig,
+    type SSRClientConfig,
+} from './client/'
+
+// ============================================================================
+// Errors
+// ============================================================================
+
+export {
+    DjangoError,
+    type FunctionErrorResponse,
+    type ErrorCode,
+} from './errors'
+
+// ============================================================================
+// Forms (typed form hooks core)
+// ============================================================================
+
+export {
+    // Single form
+    useMizanFormCore,
+    // Legacy alias
+    useMizanFormCore as useDjangoFormCore,
+    type DjangoFormState,
+    type FormSchema,
+    type FormErrors,
+    type FormOptions,
+    type FormSubmitResult,
+    type FormCoreConfig,
+    // Formset
+    useMizanFormsetCore,
+    // Legacy alias
+    useMizanFormsetCore as useDjangoFormsetCore,
+    type DjangoFormsetState,
+    type FormsetSchema,
+    type FormsetErrors,
+    type FormsetCoreConfig,
+    type FormsetSubmitResult,
+    // Shared types
+    type FieldSchema,
+    type FieldChoice,
+    type FieldError,
+    type FormMeta,
+} from './forms'