feat(export): modal task center with pause/stop controls

src/types/electron.d.ts

@@ -521,10 +521,15 @@ export interface ElectronAPI {
       estimatedSeconds: number
       sessions: Array<{ sessionId: string; displayName: string; totalCount: number; voiceCount: number }>
     }>
-    exportSessions: (sessionIds: string[], outputDir: string, options: ExportOptions) => Promise<{
+    exportSessions: (sessionIds: string[], outputDir: string, options: ExportOptions, taskId?: string) => Promise<{
       success: boolean
       successCount?: number
       failCount?: number
+      paused?: boolean
+      stopped?: boolean
+      pendingSessionIds?: string[]
+      successSessionIds?: string[]
+      failedSessionIds?: string[]
       error?: string
     }>
     exportSession: (sessionId: string, outputPath: string, options: ExportOptions) => Promise<{
@@ -536,6 +541,8 @@ export interface ElectronAPI {
       successCount?: number
       error?: string
     }>
+    pauseTask: (taskId: string) => Promise<{ success: boolean; error?: string }>
+    stopTask: (taskId: string) => Promise<{ success: boolean; error?: string }>
     onProgress: (callback: (payload: ExportProgress) => void) => () => void
   }
   whisper: {
@@ -587,7 +594,8 @@ export interface ElectronAPI {
       exportMedia?: boolean
       startTime?: number
       endTime?: number
-    }) => Promise<{ success: boolean; filePath?: string; postCount?: number; mediaCount?: number; error?: string }>
+      taskId?: string
+    }) => Promise<{ success: boolean; filePath?: string; postCount?: number; mediaCount?: number; paused?: boolean; stopped?: boolean; error?: string }>
     onExportProgress: (callback: (payload: { current: number; total: number; status: string }) => void) => () => void
     selectExportDir: () => Promise<{ canceled: boolean; filePath?: string }>
     getSnsUsernames: () => Promise<{ success: boolean; usernames?: string[]; error?: string }>