chore: introduce a .rustfmt.toml file with configs for automatic formatting (#115)

Author: rklaehn

.rustfmt.toml

@@ -0,0 +1,15 @@
+edition                     = "2024"
+unstable_features           = true
+imports_granularity         = "Crate"
+group_imports               = "StdExternalCrate"
+reorder_imports             = true
+format_code_in_doc_comments = true
+force_explicit_abi          = true
+max_width                   = 100
+merge_derives               = true
+newline_style               = "Unix"
+remove_nested_parens        = true
+reorder_modules             = true
+use_field_init_shorthand    = false
+use_small_heuristics        = "Default"
+use_try_shorthand           = false