feat: rewrite ManualExtractor progress to spec-aligned 10/50/95/100 pattern (refs #143)

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

ocr/app/extractors/manual_extractor.py

@@ -82,11 +82,12 @@ class ManualExtractor:
             logger.info(f"Progress {percent}%: {message}")
 
         try:
-            update_progress(5, "Sending PDF to Gemini for analysis")
+            update_progress(10, "Preparing extraction")
 
+            update_progress(50, "Processing with Gemini")
             gemini_result = self._engine.extract_maintenance(pdf_bytes)
 
-            update_progress(50, "Mapping service names to maintenance subtypes")
+            update_progress(95, "Mapping results")
 
             schedules: list[ExtractedSchedule] = []
             for item in gemini_result.items:
@@ -112,8 +113,6 @@ class ManualExtractor:
                     )
                 )
 
-            update_progress(90, "Finalizing results")
-
             processing_time_ms = int((time.time() - start_time) * 1000)
 
             logger.info(