fix: force LF line endings for SVG assets; fix remappings typo

- Add .gitattributes forcing eol=lf for img/*.svg so vm.readFile()
  base64 output is deterministic regardless of core.autocrlf / Windows
  checkout behavior. Fixes testFlipTokenToSad() failing with CRLF
  checked-out SVGs.
- Correct 'remappping' -> 'remappings' in foundry.toml (was emitting a
  build warning).

.gitattributes

@@ -0,0 +1,4 @@
+# Force LF line endings for asset files read by forge scripts (vm.readFile)
+# so the working tree always matches what's stored in git, regardless of
+# core.autocrlf / Windows checkout behavior.
+img/*.svg text eol=lf