Add initial scripts and project conventions

.gitignore

@@ -1,14 +1,17 @@
-# Editor temporary and backup files
-*~
+# Local/editor junk
+.DS_Store
+Thumbs.db
 *.swp
 *.swo
-*.bak
-.#*
+.vscode/*
+!.vscode/extensions.json
+.idea/
 
-# Temporary files and generated logs
-*.tmp
+# Script-local temp/output — scripts should write here if they need
+# scratch space, never into the repo tree itself
+tmp/
 *.log
 
-# Operating system files
-.DS_Store
-Thumbs.db
+# Local env overrides, if any script ends up needing one
+.env
+.env.local