fix: add historical import jobs to unified jobs list

Historical import jobs were not appearing in the recent jobs list because
list_letzshop_jobs() only queried marketplace_import_jobs and letzshop_sync_logs.

Changes:
- Add LetzshopHistoricalImportJob query to list_letzshop_jobs()
- Add current_phase and error_message fields to LetzshopJobItem schema
- Fixed stuck job 8 (marked as failed)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

models/schema/letzshop.py

@@ -397,10 +397,12 @@ class LetzshopVendorListResponse(BaseModel):
 
 
 class LetzshopJobItem(BaseModel):
-    """Schema for a unified job item (import, export, or order sync)."""
+    """Schema for a unified job item (import, export, order sync, or historical import)."""
 
     id: int
-    type: str = Field(..., description="Job type: import, export, or order_sync")
+    type: str = Field(
+        ..., description="Job type: import, export, order_sync, or historical_import"
+    )
     status: str = Field(..., description="Job status")
     created_at: datetime
     started_at: datetime | None = None
@@ -408,6 +410,11 @@ class LetzshopJobItem(BaseModel):
     records_processed: int = 0
     records_succeeded: int = 0
     records_failed: int = 0
+    # Historical import specific fields
+    current_phase: str | None = Field(
+        None, description="Current phase for historical imports"
+    )
+    error_message: str | None = Field(None, description="Error message if failed")
 
 
 class LetzshopJobsListResponse(BaseModel):