chore: keep the acadrust patch byte-exact in checkouts

Mark *.patch as -text so core.autocrlf never rewrites the served MPL-2.0
source patch (#1); `patch -p1` needs the original LF bytes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.gitattributes

@@ -2,3 +2,4 @@
 *.dwg binary
 *.ttf binary
 *.dxf -text
+*.patch -text