patches: review pass 3 - move block_input to origin patches

block_input protection moved from P0008 to their respective origin
patches for independent compilability (GNU Emacs requirement):
- P0001 (ns_ax_buffer_text): now has block_input + record_unwind
- P0003 (postCompletionAnnouncementForBuffer): now has block_input
- P0004 (ns_ax_scan_interactive_spans): now has block_input

P0008 now only adds its own new functionality (child frame completion
announcements, echo area announcements) without duplicating block_input
from earlier patches.

All 9 patches apply cleanly with git am on Linux git 2.43.0.

patches/0000-ns-integrate-with-macOS-Zoom-for-cursor-tracking.patch

@@ -1,7 +1,7 @@
-From cc35459697126cf2fe7d152978170fa1e152b11d Mon Sep 17 00:00:00 2001
+From d71de5bc8af58083ee024fd7117d06bf7e6cc0d0 Mon Sep 17 00:00:00 2001
 From: Martin Sukany <martin@sukany.cz>
 Date: Sat, 28 Feb 2026 22:39:35 +0100
-Subject: [PATCH 1/9] ns: integrate with macOS Zoom for cursor tracking
+Subject: [PATCH 0/8] ns: integrate with macOS Zoom for cursor tracking
 
 Inform macOS Zoom of the text cursor position so the zoomed viewport
 follows keyboard focus in Emacs.  Also track completion candidates so