feat: add message action hooks with TDD

Implement useMessageActions and useMessageUnreadCount hooks following strict TDD principles (RED → GREEN → REFACTOR).

useMessageActions provides:
- markRead(id) - mark single message as read
- batchMarkRead(ids) - batch mark messages as read
- deleteMessage(id) - delete message
- Independent loading/error states for each operation

useMessageUnreadCount provides:
- Fetch total unread count and counts by message type
- refetch() method for manual refresh
- loading and error state management

All operations use MessageController from SDK with proper error handling.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

hooks/use-message-actions.test.ts

@@ -0,0 +1,121 @@
+import { renderHook, act } from '@testing-library/react-native'
+import { useMessageActions } from './use-message-actions'
+import { root } from '@repo/core'
+import { MessageController } from '@repo/sdk'
+
+jest.mock('@repo/core', () => ({
+  root: {
+    get: jest.fn(),
+  },
+}))
+
+describe('useMessageActions', () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  describe('markRead', () => {
+    it('should mark message as read successfully', async () => {
+      const mockMessageController = {
+        markRead: jest.fn().mockResolvedValue({ message: 'success' }),
+      }
+      ;(root.get as jest.Mock).mockReturnValue(mockMessageController)
+
+      const { result } = renderHook(() => useMessageActions())
+
+      await act(async () => {
+        await result.current.markRead('msg-1')
+      })
+
+      expect(mockMessageController.markRead).toHaveBeenCalledWith({ id: 'msg-1' })
+      expect(result.current.markReadLoading).toBe(false)
+      expect(result.current.markReadError).toBeNull()
+    })
+
+    it('should handle markRead error', async () => {
+      const mockError = new Error('Failed to mark read')
+      const mockMessageController = {
+        markRead: jest.fn().mockRejectedValue(mockError),
+      }
+      ;(root.get as jest.Mock).mockReturnValue(mockMessageController)
+
+      const { result } = renderHook(() => useMessageActions())
+
+      await act(async () => {
+        await result.current.markRead('msg-1')
+      })
+
+      expect(result.current.markReadError).toEqual(mockError)
+    })
+  })
+
+  describe('batchMarkRead', () => {
+    it('should batch mark messages as read successfully', async () => {
+      const mockMessageController = {
+        batchMarkRead: jest.fn().mockResolvedValue({ message: 'success' }),
+      }
+      ;(root.get as jest.Mock).mockReturnValue(mockMessageController)
+
+      const { result } = renderHook(() => useMessageActions())
+
+      await act(async () => {
+        await result.current.batchMarkRead(['msg-1', 'msg-2'])
+      })
+
+      expect(mockMessageController.batchMarkRead).toHaveBeenCalledWith({ ids: ['msg-1', 'msg-2'] })
+      expect(result.current.batchMarkReadLoading).toBe(false)
+      expect(result.current.batchMarkReadError).toBeNull()
+    })
+
+    it('should handle batchMarkRead error', async () => {
+      const mockError = new Error('Failed to batch mark read')
+      const mockMessageController = {
+        batchMarkRead: jest.fn().mockRejectedValue(mockError),
+      }
+      ;(root.get as jest.Mock).mockReturnValue(mockMessageController)
+
+      const { result } = renderHook(() => useMessageActions())
+
+      await act(async () => {
+        await result.current.batchMarkRead(['msg-1', 'msg-2'])
+      })
+
+      expect(result.current.batchMarkReadError).toEqual(mockError)
+    })
+  })
+
+  describe('deleteMessage', () => {
+    it('should delete message successfully', async () => {
+      const mockMessageController = {
+        delete: jest.fn().mockResolvedValue({ message: 'success' }),
+      }
+      ;(root.get as jest.Mock).mockReturnValue(mockMessageController)
+
+      const { result } = renderHook(() => useMessageActions())
+
+      await act(async () => {
+        await result.current.deleteMessage('msg-1')
+      })
+
+      expect(mockMessageController.delete).toHaveBeenCalledWith({ id: 'msg-1' })
+      expect(result.current.deleteLoading).toBe(false)
+      expect(result.current.deleteError).toBeNull()
+    })
+
+    it('should handle deleteMessage error', async () => {
+      const mockError = new Error('Failed to delete')
+      const mockMessageController = {
+        delete: jest.fn().mockRejectedValue(mockError),
+      }
+      ;(root.get as jest.Mock).mockReturnValue(mockMessageController)
+
+      const { result } = renderHook(() => useMessageActions())
+
+      await act(async () => {
+        await result.current.deleteMessage('msg-1')
+      })
+
+      expect(result.current.deleteError).toEqual(mockError)
+    })
+  })
+})