fix(frontend): type the chat-service API boundary

Same treatment as the other *-service files. getById turned out to
return a different shape than the list endpoints (messages inlined),
now modeled as ChatDetail extends Chat rather than folded into one
loose type.

Also types chat-history.tsx's props (deleteChatMutation as the actual
UseMutationResult, confirm against the exported ConfirmProps, setView/
handleCreateNewChat/switchToChat against their real signatures) since
they were all any purely because nothing upstream forced them to be.

flowsint-app/src/api/chat-service.ts

@@ -1,28 +1,29 @@
 import { fetchWithAuth } from './api'
+import type { Chat, ChatDetail } from '@/types/chat'
 
 export const chatCRUDService = {
-  get: async (): Promise<any> => {
+  get: async (): Promise<Chat[]> => {
     return fetchWithAuth('/api/chats', {
       method: 'GET'
     })
   },
-  getByInvestigationId: async (investigationId: string): Promise<any> => {
+  getByInvestigationId: async (investigationId: string): Promise<Chat[]> => {
     return fetchWithAuth(`/api/chats/investigation/${investigationId}`, {
       method: 'GET'
     })
   },
-  getById: async (chatId: string): Promise<any> => {
+  getById: async (chatId: string): Promise<ChatDetail> => {
     return fetchWithAuth(`/api/chats/${chatId}`, {
       method: 'GET'
     })
   },
-  create: async (body: BodyInit): Promise<any> => {
+  create: async (body: BodyInit): Promise<Chat> => {
     return fetchWithAuth(`/api/chats/create`, {
       method: 'POST',
       body: body
     })
   },
-  delete: async (chatId: string): Promise<any> => {
+  delete: async (chatId: string): Promise<unknown> => {
     return fetchWithAuth(`/api/chats/${chatId}`, {
       method: 'DELETE'
     })

flowsint-app/src/components/chat/chat-history.tsx

@@ -1,22 +1,24 @@
 import { chatCRUDService } from '@/api/chat-service'
-import { useQuery } from '@tanstack/react-query'
+import { useQuery, type UseMutationResult } from '@tanstack/react-query'
 import { SkeletonList } from '../shared/skeleton-list'
 import { Button } from '../ui/button'
 import { ArrowLeft, Trash, Sparkles } from 'lucide-react'
 import { Chat } from '@/types'
-import { useCallback } from 'react'
+import { useCallback, type Dispatch, type SetStateAction } from 'react'
 import { formatDistanceToNow } from 'date-fns'
-import { useConfirm } from '../use-confirm-dialog'
+import { useConfirm, type ConfirmProps } from '../use-confirm-dialog'
 import { useChatState } from '@/stores/use-chat-store'
 
+type DeleteChatMutation = UseMutationResult<unknown, Error, string>
+
 const ChatHistory = ({
   setView,
   deleteChatMutation,
   handleCreateNewChat
 }: {
-  setView: any
-  deleteChatMutation: any
-  handleCreateNewChat: any
+  setView: Dispatch<SetStateAction<'chat' | 'history'>>
+  deleteChatMutation: DeleteChatMutation
+  handleCreateNewChat: () => void
 }) => {
   const { confirm } = useConfirm()
   const setCurrentChatId = useChatState((s) => s.setCurrentChatId)
@@ -98,9 +100,9 @@ const ChatItem = ({
   switchToChat
 }: {
   chat: Chat
-  confirm: any
-  deleteChatMutation: any
-  switchToChat: any
+  confirm: (props: ConfirmProps) => Promise<boolean>
+  deleteChatMutation: DeleteChatMutation
+  switchToChat: (chatId: string) => void
 }) => {
   const handleDeleteChat = useCallback(
     async (e: { stopPropagation: () => void }) => {

flowsint-app/src/components/use-confirm-dialog.tsx

@@ -23,7 +23,7 @@ import React, {
 const defaultFunction = (): Promise<boolean> => Promise.resolve(true)
 
 // Define the props that the ConfirmDialog will use
-interface ConfirmProps {
+export interface ConfirmProps {
   title: string
   message: string
 }

flowsint-app/src/types/chat.ts

@@ -36,6 +36,11 @@ export interface Chat {
   last_updated_at: string
 }
 
+// getById returns the chat's messages inline, unlike the list endpoints.
+export interface ChatDetail extends Chat {
+  messages: ChatMessage[]
+}
+
 export function toUIMessage(msg: ChatMessage): UIMessage {
   return {
     id: msg.id,