style: Migrate to stable-only rustfmt configuration

- Remove nightly-only features from .rustfmt.toml and vendor/ss58-registry/rustfmt.toml
- Removed features: imports_granularity, wrap_comments, comment_width,
  reorder_impl_items, spaces_around_ranges, binop_separator,
  match_arm_blocks, trailing_semicolon, trailing_comma
- Format all 898 affected files with stable rustfmt
- Ensures long-term reliability without nightly toolchain dependency

bizinikiwi/pezframe/alliance/src/migration.rs

@@ -108,8 +108,8 @@ pub(crate) mod v1_to_v2 {
 			.len()
 			.saturating_add(fellows_vec.len())
 			.saturating_add(allies.len())
-			.saturating_add(retiring.len()) ==
-			0
+			.saturating_add(retiring.len())
+			== 0
 		{
 			return T::DbWeight::get().reads(4);
 		}