improve: add README, .editorconfig, fix fallback models in setup_all.py, update .gitignore

.editorconfig

@@ -0,0 +1,26 @@
+# EditorConfig helps maintain consistent coding styles across editors and IDEs
+# https://editorconfig.org
+
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+max_line_length = 100
+
+[*.{py,pyi}]
+indent_style = space
+indent_size = 4
+
+[Makefile]
+indent_style = tab
+
+[*.{nix}]
+indent_style = space
+indent_size = 2
+
+[*.md]
+trim_trailing_whitespace = false
+max_line_length = 0