Record verified Windows archive extraction helper evidence

docs/EXTRACTION-ISOLATION.md

@@ -171,3 +171,10 @@ passed normally and under Python `-O`, including missing, stale, tampered and
 architecture-mismatched helpers plus failed builds and preserved unrelated files.
 Linux headless packaging and native macOS helper staging remain open. A complete
 updated Windows archive/installer has not yet been verified or published.
+
+Updated optimized desktop build passed with the required helper verification.
+The Windows archive built successfully; all 41 size/hash records matched
+its actual entries. The helper extracted from that archive passed genuine PDF
+indexing through the normal adapter (1.76 s). Archive SHA-256:
+`760259bbf07ed076857f0e47c0b536eb352e4d00973701bfe115d95f41989daf`.
+This archive is local evidence; a new installer has not been published.