Untrack binary driver/installer payloads

Adds .cab, .sys, .dll, .inf, .cat, .dl_, .da_, .ch_, .in_, .ex_, .ds_,
.msp, .mst, and Thumbs.db to .gitignore. Removes 575 previously-tracked
binary files from the index (files remain on disk, just no longer version
controlled). Keeps .iss/.ps1/.md/.config source tracked.

.gitignore

@@ -1,5 +1,19 @@
 *.exe
 *.zip
 *.msi
+*.msp
+*.mst
+*.cab
+*.sys
+*.dll
+*.inf
+*.cat
+*.dl_
+*.da_
+*.ch_
+*.in_
+*.ex_
+*.ds_
+Thumbs.db
 Output/
 .claude/