Add .gitattributes: force LF everywhere (CRLF breaks OpenWrt scripts/Makefiles)

.gitattributes

@@ -0,0 +1,17 @@
+# Force LF on all text files. CRLF in OpenWrt shell scripts / Makefiles / Go
+# breaks busybox ash and the build. This repo is LF-only, regardless of OS.
+* text=auto eol=lf
+
+*.sh    text eol=lf
+*.go    text eol=lf
+*.uc    text eol=lf
+*.js    text eol=lf
+*.json  text eol=lf
+*.md    text eol=lf
+*.nft   text eol=lf
+*.conf  text eol=lf
+Makefile text eol=lf
+go.mod  text eol=lf
+
+# init.d / hotplug / uci-defaults scripts have no extension — force LF
+package/**/files/etc/** text eol=lf