refactor(admin): split lib/sdk/context.tsx (1280 LOC) into focused modules

Extract the monolithic SDK context provider into seven focused modules:
- context-types.ts (203 LOC): SDKContextValue interface, initialState, ExtendedSDKAction
- context-reducer.ts (353 LOC): sdkReducer with all action handlers
- context-provider.tsx (495 LOC): SDKProvider component + SDKContext
- context-hooks.ts (17 LOC): useSDK hook
- context-validators.ts (94 LOC): local checkpoint validation logic
- context-projects.ts (67 LOC): project management API helpers
- context-sync-helpers.ts (145 LOC): sync infrastructure init/cleanup/callbacks
- context.tsx (23 LOC): barrel re-export preserving existing import paths

All files under the 500-line hard cap. Build verified with `npx next build`.

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

admin-compliance/lib/sdk/context-sync-helpers.ts

@@ -0,0 +1,145 @@
+import React from 'react'
+import { SDKState } from './types'
+import { SDKApiClient, getSDKApiClient, resetSDKApiClient } from './api-client'
+import { StateSyncManager, createStateSyncManager, SyncState, SyncCallbacks } from './sync'
+import { ExtendedSDKAction } from './context-types'
+
+// =============================================================================
+// SYNC CALLBACK BUILDER
+// =============================================================================
+
+/**
+ * Builds the SyncCallbacks object used by the StateSyncManager.
+ * Keeps the provider component cleaner by extracting this factory.
+ */
+export function buildSyncCallbacks(
+  setSyncState: React.Dispatch<React.SetStateAction<SyncState>>,
+  setIsOnline: React.Dispatch<React.SetStateAction<boolean>>,
+  dispatch: React.Dispatch<ExtendedSDKAction>,
+  stateRef: React.MutableRefObject<SDKState>
+): SyncCallbacks {
+  return {
+    onSyncStart: () => {
+      setSyncState(prev => ({ ...prev, status: 'syncing' }))
+    },
+    onSyncComplete: (syncedState) => {
+      setSyncState(prev => ({
+        ...prev,
+        status: 'idle',
+        lastSyncedAt: new Date(),
+        pendingChanges: 0,
+      }))
+      if (syncedState.lastModified > stateRef.current.lastModified) {
+        dispatch({ type: 'SET_STATE', payload: syncedState })
+      }
+    },
+    onSyncError: (error) => {
+      setSyncState(prev => ({
+        ...prev,
+        status: 'error',
+        error: error.message,
+      }))
+    },
+    onConflict: () => {
+      setSyncState(prev => ({ ...prev, status: 'conflict' }))
+    },
+    onOffline: () => {
+      setIsOnline(false)
+      setSyncState(prev => ({ ...prev, status: 'offline' }))
+    },
+    onOnline: () => {
+      setIsOnline(true)
+      setSyncState(prev => ({ ...prev, status: 'idle' }))
+    },
+  }
+}
+
+// =============================================================================
+// INITIAL STATE LOADER
+// =============================================================================
+
+/**
+ * Loads SDK state from localStorage and optionally from the server,
+ * dispatching SET_STATE as appropriate.
+ */
+export async function loadInitialState(params: {
+  storageKey: string
+  enableBackendSync: boolean
+  projectId?: string
+  syncManager: StateSyncManager | null
+  apiClient: SDKApiClient | null
+  dispatch: React.Dispatch<ExtendedSDKAction>
+}): Promise<void> {
+  const { storageKey, enableBackendSync, projectId, syncManager, apiClient, dispatch } = params
+
+  // First, try loading from localStorage
+  const stored = localStorage.getItem(storageKey)
+  if (stored) {
+    const parsed = JSON.parse(stored)
+    if (parsed.lastModified) {
+      parsed.lastModified = new Date(parsed.lastModified)
+    }
+    dispatch({ type: 'SET_STATE', payload: parsed })
+  }
+
+  // Then, try loading from server if backend sync is enabled
+  if (enableBackendSync && syncManager) {
+    const serverState = await syncManager.loadFromServer()
+    if (serverState) {
+      const localTime = stored ? new Date(JSON.parse(stored).lastModified).getTime() : 0
+      const serverTime = new Date(serverState.lastModified).getTime()
+      if (serverTime > localTime) {
+        dispatch({ type: 'SET_STATE', payload: serverState })
+      }
+    }
+  }
+
+  // Load project metadata (name, status, etc.) from backend
+  if (enableBackendSync && projectId && apiClient) {
+    try {
+      const info = await apiClient.getProject(projectId)
+      dispatch({ type: 'SET_STATE', payload: { projectInfo: info } })
+    } catch (err) {
+      console.warn('Failed to load project info:', err)
+    }
+  }
+}
+
+// =============================================================================
+// INIT / CLEANUP HELPERS
+// =============================================================================
+
+export function initSyncInfra(
+  enableBackendSync: boolean,
+  tenantId: string,
+  projectId: string | undefined,
+  apiClientRef: React.MutableRefObject<SDKApiClient | null>,
+  syncManagerRef: React.MutableRefObject<StateSyncManager | null>,
+  callbacks: SyncCallbacks
+): void {
+  if (!enableBackendSync || typeof window === 'undefined') return
+
+  apiClientRef.current = getSDKApiClient(tenantId, projectId)
+  syncManagerRef.current = createStateSyncManager(
+    apiClientRef.current,
+    tenantId,
+    { debounceMs: 2000, maxRetries: 3 },
+    callbacks,
+    projectId
+  )
+}
+
+export function cleanupSyncInfra(
+  enableBackendSync: boolean,
+  syncManagerRef: React.MutableRefObject<StateSyncManager | null>,
+  apiClientRef: React.MutableRefObject<SDKApiClient | null>
+): void {
+  if (syncManagerRef.current) {
+    syncManagerRef.current.destroy()
+    syncManagerRef.current = null
+  }
+  if (enableBackendSync) {
+    resetSDKApiClient()
+    apiClientRef.current = null
+  }
+}