feat: add scratchpad to frontend types and API client

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

frontend/src/api/sessions.ts

@@ -46,6 +46,11 @@ export const sessionsApi = {
     const response = await apiClient.post<string>(`/sessions/${id}/export`, options)
     return response.data
   },
+
+  async updateScratchpad(id: string, content: string): Promise<Session> {
+    const response = await apiClient.patch<Session>(`/sessions/${id}/scratchpad`, { scratchpad: content })
+    return response.data
+  },
 }
 
 export default sessionsApi

frontend/src/types/session.ts

@@ -40,6 +40,7 @@ export interface Session {
   ticket_number: string | null
   client_name: string | null
   exported: boolean
+  scratchpad: string
 }
 
 export interface SessionCreate {
@@ -54,6 +55,7 @@ export interface SessionUpdate {
   custom_steps?: CustomStep[]
   ticket_number?: string
   client_name?: string
+  scratchpad?: string
 }
 
 export interface SessionExport {