Remove LocalPreferences.toml and add to .gitignore

- Remove LocalPreferences.toml from repository (contains user-specific preferences)
- Add LocalPreferences.toml to .gitignore to prevent future commits
- Preferences should be generated locally by users, not committed to repo

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: ChrisRackauckas

.gitignore

@@ -3,6 +3,7 @@
 *.jl.mem
 /docs/build/
 Manifest.toml
+LocalPreferences.toml
 
 *.swp
 .vscode