refactor(electron): remove redundant generateIncrementalSessions calls after incremental import

Session index is now built inside the shared incremental-importer, so the
explicit post-import worker.generateIncrementalSessions(sessionId) calls in
the Desktop layer were no-ops. Remove all four call sites.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/desktop/main/api/adapters.ts

@@ -129,11 +129,6 @@ export class WorkerImporter implements DataImporter {
     const result = await worker.incrementalImport(sessionId, tempFile)
     if (result.success) {
       this.logger.info(`[Pull] Incremental OK: +${result.newMessageCount} messages`)
-      try {
-        await worker.generateIncrementalSessions(sessionId)
-      } catch {
-        /* ignore */
-      }
       return { success: true, newMessageCount: result.newMessageCount, sessionId }
     }
     if (result.error === 'error.session_not_found' || result.error?.includes('no such table')) {

apps/desktop/main/api/routes/import.ts

@@ -264,11 +264,6 @@ async function handleUnifiedImport(request: FastifyRequest, reply: FastifyReply,
       const result = await worker.incrementalImport(sessionId, tempFile, undefined, importOptions)
 
       if (result.success) {
-        try {
-          await worker.generateIncrementalSessions(sessionId)
-        } catch {
-          // non-blocking
-        }
         notifySessionListChanged()
         const responsePayload = successResponse({
           sessionId,
@@ -390,11 +385,6 @@ async function handleLegacyImport(request: FastifyRequest, reply: FastifyReply,
       const result = await worker.incrementalImport(sessionId, tempFile, undefined, importOptions)
 
       if (result.success) {
-        try {
-          await worker.generateIncrementalSessions(sessionId)
-        } catch {
-          // non-blocking
-        }
         notifySessionListChanged()
         reply.send(
           successResponse({

apps/desktop/main/ipc/chat.ts

@@ -283,11 +283,6 @@ export function registerChatHandlers(ctx: IpcContext): void {
       })
 
       if (result.success) {
-        try {
-          await worker.generateIncrementalSessions(sessionId)
-        } catch (e) {
-          console.error('[IpcMain] Failed to incrementally generate session index:', e)
-        }
         // 分析缓存按 DB 文件版本自动失效，无需手动清理
         // 通知渲染进程刷新会话列表（与 API 路由的 notifySessionListChanged 保持一致）
         win.webContents.send('api:importCompleted')